Make an equation system based on the problem eg. a is the first number and b is the seond number An equation for "The sum of two numbers is 53" is ⇒ a + b = 53 An equation for "twice the first number minus three times the second number is 26" ⇒ 2a - 3b = 26 Solve the equations by elimination and subtitution method Eliminate a to find the value of b a + b = 53 (multiplied by 2) 2a - 3b = 26 -------------------------------------- 2a + 2b = 106 2a - 3b = 26 ------------------- - (substract) 5b = 80 b = 80/5 b = 16
Subtitute the value of b to one of the equations a + b = 53 a + 16 = 53 a = 53 - 16 a = 37
