Hi! I'm happy to help!
First, we need to get our two equations, so we need to look at what facts we have throughout the equation. It tells us that x is 3 times as much as y. We can use this to write our first equation:
3y=x
All of the interior angles inside of a triangle add up to 180°, and because we already have 3 angles, we can use this information to make our second equation:
x+y+45=180
Now, we have to use these equations together to get our answer.
Since we can replace 3y for x (first equation) we can replace it in our second equation:
3y+y+45=180
We edit both sides of the equation in the same way to get the same outcome, but to simplify. Since we are solving for y, let's isolate it by subtracting 45 from both sides:
3y+y+45=180
-45 -45
3y+y=135
Let's combine the 3y and y to make things simpler:
4y=135
From here, we divide both sides by 4, to isolate y:
y=33.75
Now that we have our y value, we can use our first equation to solve for x:
3y=x
3(33.75)=x
101.25=x
We used our equations to get both our x and y values: 33.75, and 101.25.
I hope this was helpful, keep learning! :D
