Answer:
y = 5
Step-by-step explanation:
The sum of all three angle measures of a triangle is ALWAYS equivalent to 180 degrees. Using this information, (4y + 10) + 75 + (3x) = 180
This is also an equilateral triangle, meaning those bottom two angles will be equivalent. 75 = 3x
So you can plug in the value for 3x into the first equation: (4y + 10) + 75 + 75 = 180
First, simplify the equation by adding the 75 and 75 together: (4y + 10) + 150 = 180
Now, subtract 150 from both sides of the equation: 4y + 10 = 30
Then subtract 10 from both sides: 4y = 20
And divide both sides by 4: y = 5
I hope this helps!
