Here's an identity

a(3x-10) = 21x+2b

work out the value of a and b

to find the perimeter of the rectangle this is the expression:

x-9+x-9+3x-4+3x-4=138

if we simplify it:

8x-26=138

remember, 138 is what it all adds up to

the length is 11.5cm

the width is 57.5cm

the area is 661.25cm^2

the answers might not be correct use at own risk

the answer will be b x² +x-1

step-by-step explanation:

whats the rest of it?