2. Given two consecutive positive EVEN integers, the square of the largest minus
10 times the smaller is 76. What is the sum of the two integers?

2 Given two consecutive positive EVEN integers the square of the largest minus 10 times the smaller is 76 What is the sum of the two integers class=

Respuesta :

Answer:

26

Step-by-step explanation:

2. Given two consecutive positive EVEN integers, the square of the largest minus 10 times the smaller is 76. What is the sum of the two integers?

I'll call the two integers a and b.    a=b+2

a² - 10b = 76

(b+2)² - 10b =76

(b+2)(b+2) -10b = 76

b² +2b + 2b +4  -10b = 76

b² +4b + 4  -10b  = 76

b² -6b + 4 =76  subtract 76 from both sides to get the right side equal to zero

b² -6b +4 -76 = 0

b² -6b - 72 = 0  what factors of -72 add up to -6? The two that work are -12, 6

(b-12)(b+6) = 0   so  b-12  = 0   or b+6  =  0

                                 +12  +12         -6     -6

                                  b = 12      or     b = -6  but b must be positive so b=12, a=14  

a+b= 14+12 = 26

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