Explanation:
First, we need to find that top angle, which we'll call angle x. We can say 26 is the hypotenuse, and 12 is the adjacent, so we know that:
Let's solve this, to find X:
Now that we know what X is, we can use trig to find the missing side, which we'll call y. 48 is the adjacent, and y is the hypotenuse, therefore:
To find y, let's rearrange:
And now let's figure out calculate the value of y (I'm leaving the value of X as just X for the equations, but you will need it to calculate first):