For the equation, 5(7x + 8) + 3(2x + b) ≡ ax + 13. Find the values of a and b. You may use a calculator.

By expanding the brackets on the left hand side of the equation you get,35x + 40 + 6x + 3b and by simplifying you get 41x + 40 + 3b.by comparing the x and constant terms on either side you find that a = 41, and3b + 40 = 13, rearranging b = -9.