What is the value of y?

40°

Step-by-step explanation:

We know that a triangle is equal to 180°

Since one angle is 50° we can figure out that the rest of the angles are equal to 130° (180° - 50°)

If we use 40° then 2·(40°) = 80°

and the second angle is 40° + 10° = 50°

if we add all the angles (80° + 50° + 50°) we get 180° which is correct.

B

Step-by-step explanation:

it's equivalent, so we can say that its equal.

let's call the denominator x and the numerador is 18 less then denominator, x - 18.

multiply

2.x = 5.(x - 18)

2x = 5x - 90

90 = 5x - 2x

90 = 3x

x = 90/3

x = 30

so: