3. a. Simplify (2x + y) (x-7)
b. Find the truth set of 2x-3 +3 = -1

b. X=-1/2

Step-by-step explanation:

2x-3+3=-1-3 and +3 cancel each other

2x=-1 both sides divided by 2

X=-1/2

i think it's ф or x=6,-6

step-by-step explanation:

-x^2=-36

x^2=-36

ф

or

if you mean by : -(x^2)=-36

it'll be: x^2=36

x=6,x=-6

hope it'll ! have a good day!

you for asking!