X+ 6y = 15
3x + 4y= 3

x = -3

y = 3

Step-by-step explanation:

Step 1

X = 15 - 6y

Step 2

Replace x  with 15 -6y in the second eqation

3(15 - 6y) + 4y = 3

45 - 18y + 4y = 3

45 - 3 = 18y - 4y

42 = 14 y

y= 3

find x:

X = 15 - 6(3)

x = -3

The sum of each of the angles in a triangle always equals 180. We are given angles A and C so all we need to do is add them together and subtract from 180 to find the missing angle.

Angle C is 34
Angle A is 90 (that little box indicates 90)
34+90=124
180-124=56

Ange B is 56 degrees.

Hope this helps!!