2x -3y = 13
4x -y = -9
Multiply the second equation by -3 to make the coefficient of Y opposite the first equation.
4x -y = -9 x -3 = -12x + 3y = 27
Now add this to the first equation:
2x -12x = -10x
-3y +3y = 0
13 +27 = 40
Now you have :
-10x = 40
Divide each side by -10:
x = 40 / -10
x = -4
Now you have a value for x, replace that into the first equation and solve for y:
2(-4) - 3y = 13
-8 - 3y = 13
Add 8 to both sides:
-3y = 21
Divide both sides by -3:
y = 21/-3
y = -7
Now you have X = -4 and y = -7
(-4,-7)
Answer:
- as written, -57
- as perhaps intended, C. -11
Step-by-step explanation:
The expression shown evaluates as ...
7 + 32(-5 +1)/2 = 7 +32(-4)/2 = 7 -128/2 = 7 -64 = -57
_____
If we assume your "32" is supposed to be 3², or 3^2, then the expression evaluates differently:
7 +3²(-5 +1)/2 = 7 + 9(-4)/2 = 7 -36/2 = 7 -18 = -11 . . . . matches choice C
_____
When in doubt, you can have the Google calculator evaluate your expression. However, you do have to write it properly and with all the required parentheses.