In the diagram, PQR is straight line, ( m + n) = 120o and ( n + r) = 100o. Find (m + r).

Grace1244

4 years ago

If m+n=120
Making "m" subject
m=120-n --------(i)
If n+r =100
Making r subject
r= 100-n ------(ii)
Since
m +n+r = 180° ( sum of angles on a straight line equals to 180 °)
Substituting in the new values of m and r
We have:
120-n+100-n+n=180
220-n=180
n=220-180
n=40
Therefore
m=120-40=80
And
r=100-40=60
Hence, m+r=80+60=140°

MikeMusic

10 months ago

A SHORTCUT I USED FOR WHOEVER IS INTERSTED
m+n+r=180
m+n=120
n+r=100
m+r=?
(m+n)+(n+r)+(m+r) =360 ( if you look closely) because its the same as 2m+2n+2r which is 360
120+100+(m+r) =360
m+r = 360-120-100 = 140

hope this helped

Ikwuagusi

5 years ago

The question is wrong