Yes and no, it depends on whether you are willing to accept non-integers:
Square root of 90 is 9.486832981... so A^2 - 90 = (A - 9.486832981...)(A + 9.486832981...)
-90 squared is rational - it is +8100. All perfect squares are not only rational but they are integers.
9
Squares always have 4 interior angles which each measure 90°; rhombuses do not.
(-6) x (-3) = 18 (-10) x (-9) = 90 18 - 90 = -72
In a 90-degree angle of a triangle is the hypotenuse squared is equal to the sum of squares of other two sides.
90 squared = 90^(2) = 90 x 90 = 8100
90 - 90 = 0
In a 90-degree angle of a triangle is the hypotenuse squared is equal to the sum of squares of other two sides. Reasoning in mathematics. Number theory.
90 x 90 = 8100
30 minus 90 is negative 60, if I'm correct.
Squares have four sides of equal length. In rectangles, the opposite sides are equal to one another. In both shapes, the internal angles are all 90°.
No, 90 is not a square number. 81 is 9 squared and 100 is 10 squared.