Plz help ASAP will give brainliest!!!

Answer:

a. 87.5%

b. 30 g of 12 carat and 60 g of 21 carat.

Step-by-step explanation:

a. The percentage of gold in 21 carat is given by:

[tex]gold_{21} = \frac{21}{24}*100 = 87.5 \%[/tex]

b. Since the mass he wants to produce is 90 g, then the added mass of the 12 carat, "x", and the mass of the 21 carat "y", must be equal to that:

[tex]x + y = 90[/tex]

The sum of gold on each carat type must be equal to the amount of gold on the final mixture, since a 12 carat has 50% gold and a 21 carat has 87.5% gold, then we have:

[tex]0.5*x + 0.875*y = 0.75*90\\\\0.5*x + 0.875*y = 67.5\\[/tex]

We now have a system of equations which we can solve to find the necessary mass of each type.

[tex]x + y = 90 \text{ } *-0.5\\0.5*x + 0.875*y = 67.5\\\\-0.5*x - 0.5*y = -45\\0.5*x + 0.875*y = 67.5\\\\0.375*y = 22.5\\\\y = 60[/tex]

[tex]x = 90 - y = 90 - 60\\\\x = 30[/tex]

He needs 30 g of 12 carat gold and 60 g of 21 carat gold.

Answer:

a. 87.5%

b. 30 g of 12 carat and 60 g of 21 carat.

Step-by-step explanation:

a. The percentage of gold in 21 carat is given by:

b. Since the mass he wants to produce is 90 g, then the added mass of the 12 carat, "x", and the mass of the 21 carat "y", must be equal to that:

The sum of gold on each carat type must be equal to the amount of gold on the final mixture, since a 12 carat has 50% gold and a 21 carat has 87.5% gold, then we have:

We now have a system of equations which we can solve to find the necessary mass of each type.

He needs 30 g of 12 carat gold and 60 g of 21 carat gold.

Step-by-step explanation:

Answer:

V= 468 * 3.14 = 1.469.52

Step-by-step explanation:

Volume of a cylinder = π r^2 h

  V= 3.14  *6^2 * 13

   V= 1469.52 cubic unit                      

Answer:

1

Step-by-step explanation:

Answer:

2.

Step-by-step explanation:

Rational numbers can be written as a/b where a and b are integers ( b not zero) and a and b are co-prime ( no common factors)

A whole number is rational (2 for example can be written as 2/1).

It could have been 2 or 3 or 33.

Answer:

[tex]-3x^2y-xy^2-7xy-3[/tex]

Step-by-step explanation:

[tex](4xy^2-3x^2y-5xy-6)+(-5xy^2-2xy+3)[/tex]

[tex]4xy^2-3x^2y-5xy-6-5xy^2-2xy+3[/tex]

[tex]-3x^2y-xy^2-7xy-3[/tex]

Answer:

X-6

Step-by-step explanation:

Just did this one

Answer:

Sides lengths of a ,b, c such that a^2+b^2 =c^2, triangle ABC is a right triangle

Step-by-step explanation:

Sides lengths of a ,b, c such that a^2+b^2 =c^2, triangle ABC is a right triangle

The converse is interchanging what is given and what is proven.

Answer:

side lengths;a2 + b2 = c2;triangle abc is a right angle

explanation=  when you  add side lengths a and b u get c which would become a right triangle as stated in the formula a2 + b2 = c2

thats the answer mate hope it helps

Answer:

The ratios are £355 and £284

Answer:

335: 284

Step-by-step explanation:

£639 in ratio 5:4

5+4 =9

639 / 9 = 71

71 × 5 = 355

71 ×285 =284

355:284

Answer:

Right isosceles

Step-by-step explanation:

We have a right angle so the triangle is a right triangle

We have two sides that are equal so it is an isosceles triangle

Answer:

The answer is 108.

Step-by-step explanation:

This can be solved with a simple proportion. 5/12 = 45/1. For 5 to become 45, you need to multiply by 9. You do the same to the denominator. 12 times 9 is 108.

82 ÷ 15 = 5.4

Mixed number form: 5 ⁷/₁₅

Answer:

the answer is 5.4

Step-by-step explanation:

Answer:

B) ∠B ≅ ∠K

Step-by-step explanation:

The Angle-Angle-Side Postulate (AAS) states that if two angles and a non-included side of one triangle are congruent to two angles and the corresponding non-included side of another triangle, then the two triangles are congruent.

Given that ∠A ≅ ∠J and AC ≅ JL, then we need that ∠B ≅ ∠K to satisfy postulate AAS (the two angles are ∠A and ∠B in one triangle and ∠K and ∠J in the other one, and the non-included side is AC in one triangle and JL in the other one).

Answer:

A) ∠C ≅ ∠L

Step-by-step explanation: I took the test

Answer:

For x=1 substituting in f(x) the value of x

f(1)=-3(1)+1 = -2

For x=0 substituting in g(x) the value of x

g(0)=3^(0) =1

Finally, we have to find for what value of x the function f(x) gives -8

f(x) = -8

-8 = -3x+1

-3x=-9

x=3

Answer:What was done from the first to the second equation was that the fraction was simplified. 126 and 32 have a common factors of 2. 

126/32=(63*2)/(16*2)

The 2s in the top and bottom can cancel out, leaving the fraction 63/16. 

In addition, since there are x terms on the top and bottom, they cancelled out as well. 

x/x^3=1/x^2

This leaves an x^2 term on the bottom. 

Thus, if a is 16, and b is 2, you will have an equivalent form of the fraction.

Step-by-step explanation:

Answer:

A=16 & B=2

Second part is B

Step-by-step explanation:

;)

Answer:

75

Step-by-step explanation:

Answer:

75wpm

Step-by-step explanation:

150 ÷ 2 = 75

75 wpm

C. Find the sum of the two horizontal in the summer for two vertical vectors.

Answer:

Can confirm C is right i got 100 on the unit test

Step-by-step explanation:

Answer:

I think that it’s correct

Step-by-step explanation:

Answer:

Vlad did not make a mistake

Step-by-step explanation:

Khan academy 7th grade inequalities quiz 2 and unit test

Answer:

[tex]2.\ f(x) = \frac{3}{4}x^2 + 2x - 5[/tex]

Step-by-step explanation:

Given

[tex]f(x) = -8x^3 - 16x^2 - 4x\\f(x) = \frac{3}{4}x^2 + 2x - 5\\f(x) = \frac{4}{x^2} - \frac{2}{x} + 1\\f(x) = 0x^2 - 9x + 7[/tex]

Required

Which of the above is a quadratic function

A quadratic function has the following form;

[tex]ax^2 +bx + c = 0 \ where \ a\neq 0[/tex]

So, to get a quadratic function from the list of given options, we simply perform a comparative test of each function with the form of a quadratic function

[tex]1.\ f(x) = -8x^3 - 16x^2 - 4x[/tex]

This is not a quadratic function because it follows the form [tex]f(x) = ax^3 + bx^2 + c[/tex] and this is different from [tex]ax^2 +bx + c = 0 \ where \ a\neq 0[/tex]

[tex]2.\ f(x) = \frac{3}{4}x^2 + 2x - 5[/tex]

This function has an exact match with [tex]ax^2 +bx + c = 0 \ where \ a\neq 0[/tex]

By comparison; [tex]a = \frac{3}{4}\ b = 2\ and\ c = -5[/tex]

[tex]3.\ f(x) = \frac{4}{x^2} - \frac{2}{x} + 1[/tex]

This is not a quadratic function because it follows the form [tex]f(x) = \frac{a}{x^2} + \frac{b}{x} + c[/tex] and this is different from [tex]ax^2 +bx + c = 0 \ where \ a\neq 0[/tex]

[tex]4.\ f(x) = 0x^2 - 9x + 7[/tex]

This is not a quadratic function because it follows the form [tex]f(x) = ax^2 +bx + c = 0\ but\ a = 0[/tex]

Unlike the quadratic function where [tex]a\neq 0[/tex]

So, from the list of given options, only [tex]2.\ f(x) = \frac{3}{4}x^2 + 2x - 5[/tex] satisfies the given condition

Answer:

#1

Step-by-step explanation:

#1)-3-1.5

you go 3 units left from zero to get to -3

then, you go 1.5 units to the left of -3,

thus getting to -4.5,

#2) in #2 you went to the right to 3 and 4.5, but dude, it is subtraction, so, it should go the opposite way...wrong

#3) you can't change to order of the things in subtraction like in addition, so #3 is wrong answer of 3

#4) like in # 3, you have to go from 0 to (-3)   3 units to the left first, also you go from -3 to -4.5 1.5 units to the left, not -3 to -1.4 -4.5, which makes no sense, steps shown incorrectly to get any single answer at all

#5) you go from -1.5 to 1.5 , then from 0 to -1.5, same as in 4, 3, and 2 you will never get to -4.5, but same as 4 not get any single answer at all

Answer:

12

Step-by-step explanation:

Answer:

It is irrational because a rational number expressed as the quotient or fraction  of two integers

Step-by-step explanation:

Answer:

h=14

Step-by-step explanation:

3/4*1/4=3/16

21/32/(3/16)=14

Answer:

h=25

Step-by-step explanation:

Answer:

31.2 dm

Step-by-step explanation:

Podemos calcular a hipotenusa do triángulo empregando a regra de Pitágoras:

[tex]h^2 = a^2 + b^2[/tex]

onde h = hipotenusa

a = unha perna do triángulo

b = outra perna do triángulo

Polo tanto:

[tex]h^2 = 20^2 + 24^2\\\\h^2 = 400 + 576\\\\h^2 = 976\\\\h = \sqrt{976}\\ \\h = 31.2 dm[/tex]

A hipotenusa é de 31,2 dm

Answer:

216 2/3

Step-by-step explanation:

yoys : frents

6   :   13

We have 100 yoys

100/6 =50/3

Multiply by 50/3

yoys      : frents

6 *50/3  :   13*50/3

100         : 650/3

As a mixed number

650/3 frents

216 2/3

[tex]\frac{8}{25} = 0.32\\[/tex] when simplified into decimals.

This means that these two are equal. hope this helps!

8/25 is equal to 0.32

let me know if u need explanation

Here A is the answer because it has more terms i guess

Answer:

D) 2 points

Step-by-step explanation:

Compare a couple of points in the clumps of points and that is your answer