The Relatioship between x and y is y=5x + 18

How does the value of y change when x increses form 1 to 4?

a. y increase by 15
b. y increase by 3
c. y decresases by 3
d y dercreased by 15

Help Prettty Pleassseee !

hint: what is y when x = 4?

what is y when x = 1?

Idk . how to even do ?

I think you should plug in when x=1,2,3,4

into the eqn. then see if it increase or decrease when you finish

X=1
Plug it into the eqn.
y=5(1)+18

x=2

x=3

x=4

Get it?

the question wants you to understand the concept of rate of change or slope.

when x = 1, y = 23
when x = 4 , y = 38
so when x went from 1 to 4, a change of 3
y went from 23 to 38 , a change of 15

(notice the rate of change is 15/3 = 5, which matches the 5 in y = mx + b, in this case y = 5x + 18 )

To find out how the value of y changes when x increases from 1 to 4, we can use the equation y = 5x + 18.

Let's substitute x = 1 into the equation:
y = 5(1) + 18
y = 5 + 18
y = 23

Now, let's substitute x = 4 into the equation:
y = 5(4) + 18
y = 20 + 18
y = 38

To find how the value of y changes, we subtract the initial value of y (when x = 1) from the final value of y (when x = 4):
Final value of y - Initial value of y = 38 - 23 = 15

Therefore, the value of y increases by 15 when x increases from 1 to 4.

Hence, the correct answer is (a) y increases by 15.