Answer:
D
Step-by-step explanation:
Remember
we can do anything to an equation as long as we do it to both sides
try to isolate the variable
you have 2 types
x+b=c
x/b=c
fior the first type, minus b from both sides to get
x=c-b
for the second, multiply both sides by b to get rid of the fraction to get
x=cb
also remember that -x times -1=x
b.add 25 to both sides
-a=20
multiply -1
a=-20
c.
-t/8=-4
multiply both sides by 8
-t=-32
mutiply -1
t=32
d. -n/-5=-30
mulitply both sides by -5
-n=150
multiply both sides by -1
n=-150
e. multiply both sides by 12
-l=144
multiply b y-1
l=-144
-7x - 2y = 19
4x + y = -12
Set y equal to each other (opposite signs are fine and you could also set x equal instead of y)
-7x - 2y = 19
8x + 2y = -76
Add equations together
x = -52
Plug x value into an equation
4(-52) + y = -12
Solve for y
-208 + y = -12
y = 196
Hope this helps! ;)