Answer:
Option B is not a justification
Step-by-step explanation:
Option A is a justification (to get two pair of similar triangles (ABC-ACD) and (ABC-BCD))
Option C is a justification (a^2 = cy, b^2 = cx, a^2 + b^2 = cy + cx)
Option D is a justification (a^2 + b^2 = cy + cx = c(y + x) = c^2)
=> Option B is not a justification
Simplified would be 21/1
Would be 21
Well theoretically speaking you could but that would take a long time and 15 and 30 have a common factor of 5 and 15. So I think for this one you can't since there are two common factors.
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Answer:
60 boys
Step-by-step explanation:
boys : girls = 3 : 5
Total number of people = 160
Let y = common factor:
Therefore, 3y + 5y = 160
⇒ 8y = 160
⇒ y = 160 ÷ 8 = 20
Boys = 3y = 3 x 20 = 60
Girls = 5y = 5 x 20 = 100
So there are 60 boys and 100 girls