Question

Can someone help me please?!?!?!

Answer 1

Answer:

see explanation

Step-by-step explanation:

you are looking for perfect square factors of the numbers under the radical sign. both numbers and the sum are irrational because they contain √5

125 = 5×25

80 = 5×16

3√125 = 3√(25×5) = 3×5√5 = 15√5

√80 = √(16×5) = 4√5

1)  15√5 + 4√5 = 19√5      the √5 is the same square root so you add the coefficients

perfect square factors are bold

4×√(25×2)×√(9×2) =

4×5×3×√(2×2) =

60×√4 =

2)  60 × 2 = 120

the numbers are both irrational but the answer is rational because √2 ×√2 = √4 = 2