Artaud noticed that if he takes the opposite of his age and adds 39 he gets the number 24. How old is Artaud?

  15

Step-by-step explanation:

Let 'a' represent Artaud's age. He notices the relationship ...

  -a +39 = 24

If we add a-24 to both sides, we get ...

  15 = a

Artaud is 15 years old.

15 years old

Step-by-step explanation:

Let x be Artaud's age. Let the opposite of his age be -x

-x + 39 = 24

-x = 24-39

-x = -15 (multiply both sides by -1)

x = 15 years old

36 girls

step-by-step explanation:

the 48 boys is 4 parts of the ratio

divide 48 by 4 to obtain one part of the ratio

= 12 ← 1 part of the ratio

3 parts = 3 × 12 = 36 ← number of girls

c. y = 1/4 x + 5

step-by-step explanation:

first, put the equation of the line on the graph into slope-intercept form

(y = mx + b):   y = -4x + 8

second, a perpendicular line has to have "an opposite/reciprocal slope" to the original slope. so, find the "m" value in your original equation (it's -4, right? )

original slope: m = -4   perpendicular slope: change the sign to its opposite and find the reciprocal ("flip" the number)

new slope is now positive (b/c the original slope was negative 4), and it's 1/4 (not the original slope of 4 or 4/1)