The law of cosines is used for calculating one side of the triangle if the angle opposite to that side is given as well as the other sides. For this problem, we are given angle B. Therefore, the correct answer among the choices given is option 1 where a is equal to 5 and c is equal to 3.
Answer:
Each shirt cost $12
Step-by-step explanation:
First, we have to interpret this question and turn each to an equation, letting shirts represent the letter s and ties represent the letter t.
6 shirts and 3 ties cost $79.50 would be interpreted to 6s+3t=79.5 ,and 3 shirts and 2 ties cost $41 would be interpreted to 3s+2t=41
Hence we have two equations, and we solve them simultaneously.
6s+3t=79.5 (Equation 1)
3s+2t=41 (Equation 2)
We can either use the substitution method or the elimination method but for the sake of this question, we use the Elimination method.
6s+3t=79.5 (Equation 1)
3s+2t=41 (Equation 2)
We multiply equation 1 by 2 and we multiply equation 2 by 3, I'm prefer to eliminate the
2(6s+3t=79.5)
12s+6t=159 Equation 3
3(3s+2t=41)
9s+6t=123 Equation 4
We subtract equation 4 from equation 3.
12s+6t=159
9s+6t=123
12s-9s=3s
6t-6t=0
159-123=36
We therefore have
3s=36
Divide both sides by 3
s=36/3
s=12
One shirt cost $12
The answer is the last option!
17’
in 1st figure
2:1=(x+2):2
2/1=(x+2)/2
4=x+2
x=2.
Similarly in the 2nd figure
8:5=(8+3):(5+x)
8/5 = 11/ (5+x)
8(5+x) =55
40+8x=55
8x=15
x=15/8
x=1.875
Total divided by number of rows=number per row
63/7=9
9 per row
