The dimensions of triangle a are four times the dimensions of triangle b. the area of triangle b is 21 cm2. what is the area of triangle a?

X+ y = 5 ; x - y =3 solve using linear combination

Solve the following simultaneous equation by using an algebraic method (either substitution or elimination) 2x + 3y=-4 4x-y=11

Find the least common multiple of the expressions: 1. 3x^2, 6x - 18 2. 5x, 5x(x +2) 3. x^2 - 9, x + 3 4. x^2 - 3x - 10, x + 2 explain if possible