Question

Which ordered pair in the form (a, b) is a solution of this equation?

4a – 5b = 24


A.
(0, 6)

B.
(–5, –2)

C.
(6, 0)

D.
(–2, –5)

Answer 1

\(\large\color{ black}{\large {\bbox[5pt, white ,border:2px solid white ]{ \rm W}}}\)\(\large\color{ black}{\large {\bbox[5pt, white ,border:2px solid white ]{ \rm E}}}\)\(\large\color{ black}{\large {\bbox[5pt, white ,border:2px solid white ]{ \rm L}}}\)\(\large\color{ black}{\large {\bbox[5pt, white ,border:2px solid white ]{ \rm C}}}\)\(\large\color{ black}{\large {\bbox[5pt, white ,border:2px solid white ]{ \rm O}}}\)\(\large\color{ black}{\large {\bbox[5pt, white ,border:2px solid white ]{ \rm M}}}\)\(\large\color{ black}{\large {\bbox[5pt, white ,border:2px solid white ]{ \rm E}}}\)
\(\large\color{ black}{\large {\bbox[5pt, white ,border:2px solid white ]{ \rm T}}}\)\(\large\color{ black}{\large {\bbox[5pt, white ,border:2px solid white ]{ \rm O}}}\)
\(\large\color{ white}{\large {\bbox[5pt,#00c5ff ,border:2px solid white ]{ \rm O}}}\)\(\large\color{ white}{\large {\bbox[5pt,#00c5ff ,border:2px solid white ]{ \rm P}}}\)\(\large\color{ white}{\large {\bbox[5pt,#00c5ff ,border:2px solid white ]{ \rm E}}}\)\(\large\color{ white}{\large {\bbox[5pt,#00c5ff ,border:2px solid white ]{ \rm N}}}\)\(\large\color{ white}{\large {\bbox[5pt,#92dba2 ,border:2px solid white ]{ \rm S}}}\)\(\large\color{ white}{\large {\bbox[5pt,#92dba2 ,border:2px solid white ]{ \rm T}}}\)\(\large\color{ white}{\large {\bbox[5pt,#92dba2 ,border:2px solid white ]{ \rm U}}}\)\(\large\color{ white}{\large {\bbox[5pt,#92dba2 ,border:2px solid white ]{ \rm D}}}\)\(\large\color{ white}{\large {\bbox[5pt,#92dba2 ,border:2px solid white ]{ \rm Y}}}\)

We can plug in the different answer choices into the equation given in the problem :)

Let's start with Choice A :)

(0, 6) - Since it says (a, b) in the problem, we now that 0 = a and b = 6, so we can plug in our information into this equation given :
4a - 5b = 24
4*0 - 5*6 = 24

Following the order of operations, we must multiply first starting from the left side of the equation, so can you tell me what is 4*0?

Answer 2

0

Answer 3

Great! So now we have
0 - 5*6 = 24

Now still following the order of operations, we must multiply, so what is 5*6?

Answer 4

30

Answer 5

Good so we have 0 - 30 = 24, and we know that 0 - 30 is 30, but does 30 = 24? Nope! So Choice A is not our answer :(

Now for Choice B :D
(-5, -5) - Since it says (a, b) in the problem, we know that a = -5 and b = -2, so we can plug in our information into this equation given :
4a - 5b = 24
4*-5 - 5*-5 = 24

Following the order of operations, we must multiply first starting from the left side of the equation, so can you tell me what is 4*-5?

Answer 6

-20..