Question

Help please I keep getting a negative number.

Solve the system of equations algebraically using (substitution or elimination)
y=40x+95
y=50x+30

Answer 1

what did you get ?

Answer 2

What are the options? because their are multiple answers to this. @HappyBunny

Answer 3

It was a long decimal it didn't make sense so i erased it

Answer 4

do you want to use substitution or elimination ?

Answer 5

elimination

Answer 6

in that case subtract the two equations
y=40x+95
- ( y=50x+30)
--------------
y-y = 40x - 50x +95 -30

can you simplify that ?

Answer 7

-10x+65 ?

Answer 8

ok, but you should write the whole equation. on the left side you have y-y which is 0
0 = -10x +65
now add +10x to both sides

Answer 9

ohhh! x=75 and then I plug it into y=45x+95 correct?

Answer 10

?
0 = -10x +65
+10x = +10x - 10x + 65
simplify

Answer 11

on the right you simplify 10x - 10x to 0

Answer 12

so then it would just be 10x=65?

Answer 13

yes. next divide both sides by 10

\[ \frac{10x}{10} = \frac{65}{10} \]

Answer 14

you know 10/10 is 1

Answer 15

x=13/2 ?

Answer 16

yes, or x=6.5

Answer 17

Then I just plus the x into one of the equations to find Y Right?

Answer 18

yes. what do you get ?

Answer 19

I did y= 40(6.5)+95 and 260+95 y= 355

Answer 20

yes. so the answers are x= 13/2 and y=355

you can use the other equation to double check the answer

Answer 21

Thank you I've been stuck on this question for a long time

Answer 22

yw