√-45 √-70
= √-1 √45 √-1 √70 {factored √-1 out of each one}
= i√45 i√70 {working with imaginary numbers, √-1 is i}
= i√9√5 i√70 {broke √45 into √9 and √5}
= i²(3)√350 {evaluated √9 to be 3, multiplied i by i and 5 by 70}
= (-1)(3)√25√14 {in imag. numbers, i² is -1, broke 350 into 25 and 14}
= -3(5)√14 {multiplied -1 by 3 and evaluated square root of 25 to be 5}
= -15√14 {multiplied -3 by 5}
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