question_answer

Solve the following equations:

(a) 2 (x + 4) = 12

(b) 3 (x - 5) = 21

(c) 3 (x - 5) = -21

Answer:

(a) 2(x + 4) = 12

\[x+4=\frac{12}{2}\]

x + 4 = 6

x = 6 ? 4

\[\therefore \]      x = 2

(b) 3(x ? 5) = 21

\[x5=\frac{21}{3}\]

x ? 5 = 7

x = 7 + 5

\[\therefore \]     x = 12 1

(c)         3(x ? 5) = ? 21

\[x5=\frac{21}{3}\]

x ? 5 = ? 7

x = ? 7 + 5

\[\therefore \]      x = ? 2