Question

Question 3(e)

Pick out the solution from the values given in the bracket next to each equation. Show that the other values do not satisfy the equation

r - 4 = 0 (4, -4, 8, 0)

Answer 1

Given equation is r - 4 = 0.

$\begin{array}{cc}Valueofr& Valueof(r-4)\\ & \\ \left(i\right)4& 4-4=0\\ & \\ \left(ii\right)-4& -4-4=-8\\ & \\ \left(iii\right)8& 8-4=4\\ & \\ \left(iv\right)0& 0-4=-4\\ & \end{array}$

Only case (i) is satisfying the given equation.

$\therefore$ r=4 is the solution.