Jerry started doing sit-ups every day. the first day he did 15 sit-ups. every day after that he did two more sit-ups than he had done the previous day. today jerry did 33 sit-ups. write an equation that could be solved to find the number of days jerry has been doing sit-ups, not counting the first day.

33 = 15+ 2(d)

Step-by-step explanation:

d = days since we are not including the starting day

sit ups = starting + 2* days

33 = 15 +2(d)

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