Answer:
a=-1.2
Step-by-step explanation:
5x-10=3x+a=12
let's first find x:
5x-10=12
add 10 to both sides:
5x=22
divide both sides by 5:
x=4.4
now that we know what x is, we can plug it back into the equation to find a:
3*4.4+a=12
first, simplify both sides:
13.2+a=12
then, subtract 13.2 from both sides:
and our answer is: a=-1.2