The bottom one says 9/2 so with these questions, i have more on my profile.

18. Solve for x by factoring diamond method

10x^2 - 29x - 21 = 0 becomes

(2x - 7)(5x + 3) = 0

x = 7/2, -3/5

A

19. To model this we will do

(x + 9)(x + 9) = 169

distribute

x^2 + 18x - 88 = 0

factor

(x - 4)(x + 22) = 0

The length is 4m

D

20. This can be modeled by

(l)(l +5) = 234

distribute

l^2 + 5l -234 = 0

factor

(l-13)(l+18) = 0

The length is 13

The width is 18

B

21. To find this you divide the x term by 2 and square it so

10/2 = 5

5^2

25

B

22. To find this you divide the x term by 2 and square it so

9/2 = 4.5

4.5^2

81/4

C

by definition, an arc subtended by a central angle of some given measure has the same measure. so .