Mathematics: Which expression equals 6 when a = 5 and b = 1/3?

y = 7/9Step-by-step explanation:-2/9 + y is less than or equal to 5/9. -2/9 + 7/9 = 5/9...

Which expression equals 6 when a = 5 and b = 1/3?

lovemusic4

14.01.2022

Step-by-step explanation:

The given choices are

A) 9b^2 + 3a - 10

B) a^2 - 20 - 3b

C) 3(a - 2) - a + a 6b

D) 9b + ab

Now, we need to evaluate each expression and see which one gives 6 as result.

We know that a=5 and $b=\frac{1}{3}$

$9b^2 + 3a - 10=9(\frac{1}{3} )^{2}+3(5)-10=9 \times \frac{1}{9}+15-10=1+5=6$

Choice A is part of the right answer, because is equal to 6.

$a^2 - 20 - 3b=(5)^{2}-20-3(\frac{1}{3} )=25-20-1=5-1=4$

Choice B is not part of the right answer.

$3(a - 2) - a + a 6b=3(5-2)-5+5(6)(\frac{1}{3})=3(3)-5+10=9+5=14$

Choice C is not part of the answer.

$9b + ab=9(\frac{1}{3})+5(\frac{1}{3} )=3+\frac{5}{3}=\frac{9+5}{3}=\frac{14}{3}$

Therefore, the only expression which is equal to 6 when a = 5 and b = 1/3 is choice A.

0,0(0 оценок)