Help on these math problems?

Question

How do you find 12% of 64?

How do you find the slope of 4x-3y=8?

How do you evaluate -3(-5+2)?

Answer 1

to find 12% of 64 you simply make the fraction into a decimal and multiply 64 by the fractions decimal. To find the fractions decimal you just move the decimal place over to the right by two places so 64x .12= 7.68

Answer 2

How do you find 12% of 64?

12/100 = x/64

Cross multiply so you get:

100x = (12)(64)

100x = 768

x = 768/100 = 76.8 is your answer.

How do you find the slope of 4x-3y=8?

y = mx + b where m is your slope.

Rearrange your equation so it looks like that.

-3y = 8 - 4x

y = -8/3 - (4x)/(-3)

y = -8/3 + (4/3)x

so your slope is 4/3

How do you evaluate -3(-5+2)?

Remember PEMDAS.  So work on the parenthesis first.

-3(-5 + 2) = -3(-3) = 9

Answer 3

0.12 * 64 = 7.68

4x - 3y = 8 -> 3y = 4x - 8 => y = (4/3)x - 8/3

=> slope is 4/3

-3(-5 + 2) = 3 (5 - 2) = 3 * 3 = 9