Here is the answer with explanation
Answer:
C
Step-by-step explanation:
We know every triangle equals 180 so were just going to take 180 - 42 = 138 then were going to do 138 - 67 = 71 we can check our work by doing
42 + 67+ 71 = 180. We also know 67 + 42 = 109.
Lets look at our answers;
A. 109 = 180 + x When solved it gave me; x = -71. We got a positive 71 so this is incorrect.
B. x + 42 = 67 When solved it gave me; x = 25, which is incorrect.
C. x = 180 - 109 When solved it gave me; x = 71
D. 42 + 67 - x = 180 When solved it gave me; x = - 71
Therefore the answer is C.
Remark
If the lines are parallel then triangle RQS will be similar to triangle RTP
From that, all three lines in one triangle will bear the same ratio to all three lines of the second triangle.
Givens
PQ = 8
QR = 5
RS = 15
ST = x + 3
Ratio
QR/RP = RS/RT
Sub and solve
RP = 5 + 8
RP = 13
RT = 15 + x + 3
RT = 18 + x
5/13 = 15 / (18 + x) Cross multiply
5(18 + x) = 195 Remove the brackets on the left.
90 + 5x = 195 Subtract 90 from both sides.
5x = 105 Divide by 5
x = 105/5
x = 21 Answer <<<<<<<
Option I: 10 candy bars for $6.75
<span>6.75/10 = 0.68 </span>
<span>Option II: 12 candy bars for $7.25 </span>
<span>7.25 / 12 = 0.60 </span>
25/20 × 100% = 125%
125% - 100% = 25%
25% profit :)
