Answer:
y ≈18.8
Explanation:
Since this is a right triangle we can use the Pythagorean theorem
a^2 + b^2 = c^2 where a and b are the legs and c is the hypotenuse
y^2 +18^2 = 26^2
y^2 +324=676
y^2 = 676-324
y^2 =352
Taking the square root of each side
sqrt(y^2) = sqrt(352)
y is approximately 18.76
y ≈18.8