In last year’s graduating class, there were 30 more boys than girls. there were a total of 180 graduates. how many boys are in the class? how many girls are in the class?

subtract the difference first:

180-30 =150

 divide that by 2 = 150/2 =75

 so there were 75 girls

and 75+30 = 105 boys

x = ±sqrt(10)

step-by-step explanation:

5 - 2x² = -15

subtract 5 from each side

5-5 - 2x² = -15-5

-2x^2   = -20

divide by -2 on each side

-2x^2   /-2= -20/-2

x^2 =10

take the square root on each side

sqrt(x^2 )=±sqrt(10)

x = ±sqrt(10)

check:

5 - 2x² = -15

+sqrt(10)

5 - 2(sqrt(10))² = -15

5 -2(10) = -15

5 -20 = -15

-15 = -15

-sqrt(10)

5 - 2(-sqrt(10))² = -15

5 -2(10) = -15

5 -20 = -15

-15 = -15

c - they will have the same distribution

step-by-step explanation:

this is the only one that could make sense. : )