## anonymous one year ago Given that m<A= (5y+11)° , m<D = (12y-10)° , m<E = 51° , and m<F = (30y + 13). Find m<A.

1. anonymous

2. Nnesha

m<C = m<F m<A=m<D m<B=m<E |dw:1438003089618:dw| equal lines shows that m<C = m<F m<A=m<D m<B=m<E

3. anonymous

ooh, so how do I solve..?

4. Nnesha

first you need to find y so they gave m<D ,m<E ,m<F all triangles add up to 180 so set it equal to 180 $\huge\rm 12y-10+51+30y+13 =180$ solve for y

5. Nnesha

or you can set first triangle equal to 180 doesn't matter you will get the same answer m<A+m<B+m<C =180

6. anonymous

This is yet another dumb question. but is the 10 a negative and how do I add hat to 1 and 13?

7. anonymous

I meant 51, not 1 haha

8. Nnesha

9. anonymous

Ugh, this confuses me so much..

10. Nnesha

and ofc m<D is 12y negative then you have to subtract

11. Nnesha

m<F = 30y +13 m<d= 12y -10 m<E = 51 so I just replaced m<F,m<D,m<F by their values now solve for y

12. Nnesha

combine like terms 't left side first you need to find y $\huge\rm \color{reD}{12y}\color{blue}{-10}\color{blue}{+51}+\color{reD}{30y}+\color{blue}{13 }=180$

13. phi

you can think of the 12y -10 as 12y + (-10) you can re-arrange the additions to look like this 12y + 30y + (-10) +51+13 = 180 add up: 12 y's plus 30 more y's is how many y's? and the numbers: 51+13 + -10= ? you should get 42y +54= 180 now add -54 to both sides (write -54 on both sides) and then simplify