100 points
roland must purchase plywood and two-by-fours for a construction project. each sheet of plywood costs $12 and each two-by-four costs $2.50. roland can spend at most $100, and he must purchase at least 4 sheets of plywood. let x represent the number of sheets of plywood purchased. let y represent the number of two-by-fours purchased.
which inequalities are among the constraints for this situation? select each correct answer.

y > 0

x+y≥100

12x+2.5y≤100

y≥4

x≥4

2.5x+12y≤100

12x + 2.5y ≤ 100 and x ≥ 4

Step-by-step explanation:

Given that $12 is the cost for each sheet of plywood.

Then x numbers of plywood sheet will cost $12x.

Again, each two-by-four costs $2.5.

Then y numbers of two-by-four will cost $2.5y.

Now, given that Roland must purchase at least 4 sheets of plywood.

If Roland can spend at most $100, then the inequality that is among the constrains for this situation is  

12x + 2.5y ≤ 100 and x ≥ 4 (Answer)

srry idk

step-by-step explanation:

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