Answer this, it's a long overdue assignment .

13.) x=3

14.)

Step-by-step explanation:

13) plug the first equation into the second getting 3x-x-5=7 the add the x's, 4x-5=7 add five to both sides now you get 4x=12 then divide both sides by 4 getting x=3

14.) you have to add both equations vertically that gets you 5x+3y=14. then you have to solve.

5x+3y=14 subtract 3y from both sides getting 5x=14-3y divide by 5 both sides so, x=14-3y over 5 plug that into the equation and hopefully get your answers you need:)

Just learned this on my online class but I hope this helps some!

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

answer: 270

step-by-step explanation:

you have to times 200 by 1.35 to get your answer