Havesh needs to build a line of dominoes 21 1/4 in. long with each domino spaced 1 1/4 in. apart. How many will she need? Explain please and proof your answer

answer: a

step-by-step explanation:

the answer is d

the answer is in the first quadrant, which make the y-int positive.

since the dots are going down, therefore the correlation is negative

i hope it is right.

(sin 42)/31. = sinx)/37

sinx = 37 (sin42)/31

= 37× 0.66/31 = 0.787

x= 51.9

other angle opposite to y = 180-51.9-42

= 180- 93.9 =86.1

so

sin42)/31 = sin 86.1)/y

0.021 = 0.997 /y

y= 0.997/0.021 =47.47

m∠a is 90°

m∠b is 40°