We have to find b so we have to work backwards to find the answer the steps would be to find c^2 subtract that by a^2 and then you get b^2 and have to find out what multiplied by itself equals b^2 so... 85 × 85 = 7225 40 × 40 = 1600 7225 - 1600 = 5625 75 × 75 = 5625 therefore b = 75 hope that helps!
