Can anyone help me with these?

Step-by-step explanation:

Distributive property: a*(b + c)  = ab + ac

16)5x²(7 - x²) = 5x²*7 - 5x²*x²

                   =35x² - 5x⁴

17)

10x(4 - 3x) = 10x*4 - 10x*3x

                  = 40x - 30x²

18) 9( y +4) = 9*y + 9*4

                 = 9y + 36

19) 3(4 - x) - 3(2 - x) = 3*4 - 3*x -3*2 - x*(-3)

                                = 12 - 3x - 6  + 3x  {add/subtract like terms}

                                = 12 - 6 - 3x + 3x

                                = 6

20) 6y + 6(y - 4) = 6y + 6*y - 6*4

                          = 6y + 6y - 24

                          = 12y - 24

i really dont know

step-by-step explanation:

let x be the money she spent so that she can earn the free t-shirt.

since, she already spent $112.49

⇒

also, as per the statement: jennifer must spend $250 or more in order to qualify for a free t-shirt at the store.

then,

we have an inequality i.,e

subtract 112.49 from both sides we get;

therefore, $137. 51 more money does jennifer need to spend so that she can earn the free t-shirt