When you multiply a whole number by a fraction, multiply the whole number by the numerator ( top number) and then divide by the denominator (bottom number).
8 x -8/9 = (8 *-8)/9 = -64/9 = -7 1/9 = -7.1
To solve for R you use PEMDAS
Answer; c^2 = a^2 + b^2
c = 17 inches
a = 8 inches
b^2 = c^2 – a^2
b^2 = 17^2 – 8^2
b^2 = 289 – 64
b^2 = 225
b = square root of 225
b = 15 inches ≈ c.
