Answer: 1.
Step-by-step explanation: To solve for the values of a and b, we can use the quadratic formula:
x = (-b ± √(b^2 - 4ac)) / 2a
where a, b, and c are the coefficients of the quadratic equation ax^2 + bx + c = 0.
In this case, we have a = 1, b = -1, and c = -90. Plugging these values into the quadratic formula, we get:
x = (-(-1) ± √((-1)^2 - 4(1)(-90))) / 2(1)
= (1 ± √(1 + 360)) / 2
Simplifying this expression, we get:
x = (1 ± √361) / 2
= (1 ± 19) / 2
So the solutions to the equation are:
x = -9 or x = 10
Therefore, a + b = -9 + 10 = 1.