Question

In the table below, y is a linear function of x.

х
y
5
3
5
13
7
-11
What is the value of y when x = 0?

Answer 1

y= -7

Explanation:

y=ax+b

Find a where a=y2-y1 /x2-x1

y2=13,y1=5 x2=5,x1=3

substituting the values

a=13-5/5-2

a=8/2

a=4

substituting a into the formular

y=4x+b

taking x and y values let say 3 and 5 for x and y

the equation becomes

5=4(3)+b

5=12+b

5-12=b

-7=b

substituting the values of a and b into the equation

y=4x-7

when x=0

y=4(0)-7

y=0-7

y=-7

so when x=0,y=-7