There is no pattern(must be a mistake?)
When u=-2, put that in where you see "u". use parentheses.
-4(-2)+4x=12
-4*-2=8 ➡positive 8 since a negative times a negative is always positive
一一一一一
now look for x
8+4x=12
subtract 8 from both sides. get x by itself.
-8+8+4x=12-8
4x=4➡ divide both sides by 4. a number divided by itself is 1 (unless one side is negative, then the answer is negative)
4/4=1
一一一一一
x=1
I would use the process of elimination. Divide 13 from both sides
2x+7y=-57 y=-7 then plug in y to an equation
-6x-8y=80 2x+7(-7)=-57 multiple
multiple the first equation by 3 2x-49=-57 add 49 to both sides
6x+21y=-171 2x=-8 divide two from both sides
-6x-8y=80 x=-4
combine like terms So your things would be x=-4 and y=-7
13y=-91 And itd make the solution (-4,-7).
The value of x is 9.(................)