\(2x+3y=180\)
factor of 20 should be distributed to LHS and RHS (left and right hand sides) of the above expression, rewritten as \(2x+2y=180-y\), \(x+y=90-y/2\). Notice that x and y are still divisible by 20, but 90 is not divisible by 20. For 90 to be divisible by 20, it must be reduced to either 80, 60, 40 or 20
Let's pick 80 as RHS value of \(x+y=90-y/2\), then \(90-y/2=80\) and y=20
When y=20 along with \(x+y=80\), x=60. Hence, x=60 and y=20
**
If we pick 60 as nextRHS value of \(x+y=90-y/2\), then \(90-y/2=60\) and y=60
When y=60 along with \(x+y=60\), x=0. Hence, x=0 and y=60
REJECT**
Answer is
CNote: the additional solution between two up and down stars helps if the question is conversed into QC type.
Carcass wrote:
If ABC is a straight line as shown in the figure below, and the angles x & y are integer multiples of 20, what is the value of x?
Attachment:
screenshot.124.jpg
A. 20
B. 40
C. 60
d. 80
E. 100
Source:
manhattanreview