Answer:
x = -4
Step-by-step explanation:
Answer: The number is 15
Step-by-step explanation: basically the equation you should solve is
(x)+(2x)+(2x+7)=82
5x+7=82
5x= -7+82
5x=75
5/5x=75/5
x=15
I'll solve it algebraically
x+y=4
x-3y=12
multiply first equatoin by -1 and add to second
-x-y=-4
<u>x-3y=12 +</u>
0x-4y=8
-4y=8
divide both sides by -4
y=-2
sub back
x+y=4
x+-2=4
add 2 to both sides
x=6
x=6
y=-2
(6,-2)
