Which equation shows equivalent forms of the expression 21 x 2-4 ? 2^1 ×2^−4 =2^−4=−8 2^1 ×2^−4 =2^−4=1/2^4=18 2^1 ×2^−4 =2^−3=1/2^3=18 2^1 ×2^−4 =2^−3=−8

Used:

2^1 × 2^-4 = 2^-3 = 1/2^3 = 1/8

50 min

step-by-step explanation:

they will be decreasing both their times in half

60 / 2 = 30

40/2 = 20

30 + 20 = 50

the answer is true.

step-by-step explanation: