Louise buys 1 pack of pencils and 1 box of crayons for her son for $3.39. Elaine buys 7 packs of pencils and 8 boxes of crayons for her students for $25.88.

Step-by-step explanation:

p+c=3.39, p=3.39-c

7p+8c=25.88, using p=3.39-c in this equation gives you

7(3.39-c)+8c=25.88

23.73-7c+8c=25.88

23.73+c=25.88

c=2.15, since p=3.39-c

p=3.39-2.15

p=1.24

So pencils cost $1.24 and crayons cost $2.15

constants mean the stopped points or the points on a graph that nothing is changing, hope this

step-by-step explanation:

(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