Question

To find m 10 years ago

Answer 1

No no

Answer 2

Its only 5x+9=7x+3 , Thats it! and find x

Answer 3

Well.. m<C = m<D since this is an isosceles tirangle.

Answer 4

triangle*

Answer 5

^

Answer 6

so then I plug 6 into (7x+ 3) ?

Answer 7

why 6 ?
x= ??

Answer 8

Here is what you should notice:

1) the triangle is isosceles (two sides are equal... notice the red "hash marks")

2) then you should remember that the altitude (line from A to B) divides the angle at A into two equal parts (bisects the angle)

(I remember this because it looks like it divides the angle in half... (not a proof) but it jogs my memory that it does)

once you figure out the two angles are equal, you write down
that the angles equal each other.

Answer 9

you write down
7x+3 = 5x+9

once you get to this stage, you do algebra.
to find
2x= 6
x= 3

that means 1/2 of angle A is 7*3+3 (or 5*3+9) or 24 degrees

now you can find angle C using
sum of angles in a triangle is 180

24+90 + C = 180