Answer:
Step-by-step explanation:
x-y=7
-3x+9y=-39
Divide the second equation by 3
-x +3y = -13
Add this to the first equation
x-y=7
-x +3y = -13
----------------------
0x +2y = -6
Divide by 2
2y/2 = -6/2
y = -3
Now find x
x-y = 7
x -(-3) = 7
x+3 = 7
Subtract 3 from each side
x = 4
(4,-3)
Or by substitution
x-y=7
solve for x
x = 7+y
-3x+9y=-39
Substitute y+7 in for x
-3(7+y) +9y = -39
Distribute
-21 -3y +9y = -39
Combine like terms
-21 +6y = -39
Add 21 to each side
6y = -18
For #2:
<span> 3x^2 + 4 – 2x^2 + 6</span>
<span><span>You need to combine your like terms:
</span>
3x^2 – 2x^2= x^2</span>
4 + 6 = 10
This will now give you:
<span>X^2 +10</span>
Answer:
I would say the last one, bc b Is negative correct?
