Please help me i’ll mark brainliest!

Step-by-step explanation:

well if you see clously, you can see that there are actually 3 right triangles

the bigger(yellow color) and the smaller one(blue color), and the medium (right side to the smaller one)

the bigger triangle( yellow) has a 90 degrees angle

which we can subtract 27 from 90

but from where 27? well it's from the smaller triangle

so 90 - 27 = 63

the big angle is 63, but we're not finished yet!

let's make an equation:

63 = (2a+9)

subtract 9 from both sides

63 = (2a+9)

-9         -9

54 = 2a

27  = a

and we're done!

if you still in doubt

let's check it out

in the big triangle:

a + 27 + (2a + 9)  + x (angle that we don't know yet) = 180 ( all triangles is 180 degrees if you don't know)

let's subtitute the value "a"

27 + 27 + (54 + 9 ) + x = 180

54 + 63 +x = 180

117 + x = 180

subtract 117 from both sides

117 + x = 180

-117         -117

x =   63

let's subtitute to the small triangle

63 + 27 + 90 = 180

so yeah, we tried to find the small triangle and it worked, this proves that  a = 27 !

hope this helps !

30005

yes ok                                            

i will with my problems and all the other things that need to   be on by the way

step-by-step explanation: