Start with an equation summing all the angles in this triangle:
180 = <M + <N + <P
we are given <M and <N but not <P. But, since MN=NP, the angle <P is the same as the angle <M (isosceles, make a drawing to see). So
180 = 2<M + <N
180 = 2(3x+1) + x-11
180 = 7x - 9
x = 27
<P = 3*27+1 = 82 degrees
To find X, we can divide 5 into 40.
40 divided by 5 is 8.
Now we can do 5 x 8. That is 40.
X=40
OR we can do it another way.
40 divided by 5 is 8.
Cross out 5 divided by 5.
Now we have 8. Still.
X is 8
A common factor of both 126 and 399 is 3 so we can divide both numbers by 3.
126 / 3 = 42
399 / 3 = 133
A common factor for both 42 and 133 is 7 so we can divide both numbers by 7.
42 / 7 = 6
133 / 7 = 19
19 is a prime number so we can't reduce it anymore, therefore 126/399 in its simplest form is 6/19