2 brothers were born 9 years apart. the product of there ages is 6786 years. write and solve a quadratic equation, then find the sum of their ages

Quadratic equation is x² + 9x - 6786 = 0 and sum of their ages is 165.

Step-by-step explanation:

⇒ x (x +9) = 6786

⇒ x² + 9x - 6786 = 0

⇒ x = (- 9 ± √81 - 4 × 1 × - 6786)/2

⇒ x = (-9 ± √27225)/2

⇒ x = (-9 ± 165)/2

⇒ x = - 174/2 or 156/2 = - 87 or 78

⇒ x = 78 (negative value of - 87 is rejected)

Ages are x = 78 and x + 9 = 87

Sum = 78 + 87 = 165

70

step-by-step explanation:

2*5=10

4*15=60

60+10=

70

114 plus 113 times 2 and 114 times 3