Step-by-step explanation:
We have to get one positive 7y so,
4x-7y=5
9x-7y=-15
multiply anyone of the equation by -1. I choose the first one so,
4x+7y=-5
9x-7y=-15
we can now cancel the y's so the equation will be left with
-4x=-5
9x=-15
add the equations
5x=-20
divide by 5 n u get
x=-4
now plug in the x value in any one of the
equations
I choose the first one so,
4(-4)-7y=5
-16-7y=5
add 16 to both sides
-7y=21
divide by -7
y=-3.
finally check.
Answer:
-3, 1, 5, 9
Step-by-step explanation:
2(2) - 7 = -3
2(4) - 7 = 1
2(6) - 7 = 5
2(8) - 7 = 9
Answer:
I missed the part where that's my problem
Answer: 
This is the same as saying 
====================================================
Work Shown:

where 
As the steps show above, the idea is to factor the radicand into smaller pieces where one of those pieces is the largest perfect square possible. In this case, 36 is the largest factor of 180 that's a perfect square. Then I used the rule
to break up the root.
The parenthesis used at the very end is to help separate the
from the
term. The "i" is not under the square root.