5x-5=-7y
3x+2y=-8
First, you need to rearrange the first equation so it is in the same format as the second one.
5x-5=-7y
Add 5 to both sides
5x-5+5=-7y+5
Add 7y to both sides
5x+7y=-7y+7y+5
So you have 5x+7y=5
Now you need to multiply that equation by 3
3(5x+7y=5)
15x+21y=15
Multiply the second equation by -5
-5(3x+2y=-8)
-15x-10y=40
Now add them together
15x+21y=15
+(-15x-10y=40)
---------------------
11y=55
y=5
Now plug y=5 into one of the original equations and solve for x.
3x+2(5)=-8
3x+10=-8
3x=-8-10
3x=-18
x=-6
To check the solution plug them both into the other equation:
5(-6)-5=-7(5)
-30-5=-35
-35=-35
It checks.
Hope that helps.
1. y=x+3
2. y=x+3
3. y=2x+8
p.s. please leave a thanks
The average can be found by adding them all up and dividing that number by the number of items. If the result have you a number that's more than the largest or less than the lowest, you did it wrong.
(75+70+90+60+50+90+70)/7
= 505/7
=72.14
