Find the missing number___:7 = 12:21
A. 3
B. 4
C 14
D 12

B. 4 would be your answer.

Step-by-step explanation:

7 x 3 = 21

4 x 3 = 12

:)

B. 4.

Step-by-step explanation:

Let the number be x then

x/7 = 12/21

Crossmultiply:

x = 7*12 / 21

x =  12 / 3 = 4.

hope this .

r3t40

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)