In a diagram,pqr is a straight line,(m+n)=120 and (n+r)=100.find the value of (m+r)

If (m+n)=120 and (n+r)=100

means

m + n =120° and n + r = 100°

then

m + n + r = 180°

Since m + n = 120°

120 ° + r = 180°

r = 180° - 120°

r = 60°

n + r = 100°

n + 60° = 100°

n = 100° - 60°

n = 40°

Again

m + n + r = 180°

m + 40 ° + 60° = 180°

m + 100° = 180°

m = 180° - 100°

m = 80°

m + r = 80° + 60° = 140^

m + r = 80° + 60° = 140°

To find the value of (m+r), we need to determine the individual values of m, n, and r.

We are given two equations:
1. (m+n) = 120
2. (n+r) = 100

Let's solve these equations step by step:

From the first equation, (m+n) = 120, we can isolate m by subtracting n from both sides:
m = 120 - n

Now we have an expression for m in terms of n.

Next, we will substitute this expression for m into the second equation to solve for r:

(n+r) = 100
(120 - n + r) = 100 (substituting m = 120 - n into the equation)

Now, let's simplify the second equation:

120 - n + r = 100

To find the value of (m+r), we need to isolate (m+r) by performing further algebraic operations.

Let's start by subtracting 120 from both sides of the equation to eliminate the constant term:

- n + r = -20

Next, let's rearrange the equation by swapping the terms to put r in front of -n:

r - n = -20

Now, let's rearrange the equation to solve for (m+r):

r = -20 + n

Finally, let's substitute this expression for r back into the equation m = 120 - n:

m = 120 - n
= 120 - (-20 + n) (substituting r = -20 + n)

Simplifying further:

m = 120 + 20 - n
= 140 - n

Therefore, the value of (m+r) is equal to:

(m+r) = (140 - n) + (r)
= 140 + r - n

Since we don't have an explicit value for n or r, we cannot determine the exact value of (m+r).