# Q.4 (a) What should be added to $$x^2 + xy + y^2$$ to obtain $$2x^2 + 3xy?$$ (b) What should be subtracted from 2a + 8b + 10 to get -3a + 7b + 16?

(a) $$p + (x^2 + xy + y^2) = 2x^2 + 3xy$$
$$p = (2x^2 + 3xy) – (x^2 + xy + y^2)$$
$$p = 2x^2 + 3xy – x^2 – xy – y^2$$
$$p = 2x^2 – x^2 + 3xy – xy – y^2$$
$$p = x^2 + 2xy – y^2$$
(b) 2a + 8b + 10 – m = -3a + 7b + 16
m = (2a + 8b + 10) – (-3a + 7b + 16)
m = 2a + 8b + 10 + 3a – 7b – 16
m = 2a + 3a + 8b – 7b + 10 – 16
m = 5a + b – 6