Q. If 865−821=8m for some value of m, what is the value of m ?Choose 1 answer:(A) 31(B) 21(C) 1(D) 35
Recognize Base Property: Recognize that the base of all terms is 8, which allows us to use the properties of exponents to combine the terms.
Rewrite Subtraction as Division: Rewrite the subtraction of the powers as a division of the same base using the property am−an=am/an when a > 0 and a=1. 85/6−81/2=85/6/81/2
Apply Exponent Property: Apply the property of exponents that states am/an=am−n to simplify the expression.85/6/81/2=8(5/6)−(1/2)
Find Common Denominator: Find a common denominator to subtract the fractions(65) and (21). The common denominator is 6, so we rewrite (21) as (63). 8(65−63)
Subtract Fractions: Subtract the fractions.(65)−(63)=(62)
Simplify Fraction: Simplify the fraction(62) to its lowest terms.62=31
Write as Exponent: Write the simplified fraction as the exponent of 8. 81/3
Final Expression: Recognize that 81/3 is the final expression for 8m, which means m=31.
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