Question

7+5a=8a+7

Answer 1

you can do algebra, or you can think
your choice

Answer 2

or if you like we can solve it both ways

Answer 3

well i tried it this way 5a-8a=7-7 = 3=0 but thats not it

Answer 4

that is a good method, but you made one mistake

Answer 5

\[5a-8a=7-7\] is a good first step, and it is also true that \(7-7=0\)

Answer 6

but \(5a-8a\neq 3\)

Answer 7

if you have 5 thousand dollars and spend 8 thousand dollars you do not end up owing only 3 dollars

Answer 8

right

Answer 9

while it is true that \(5-8=-3\) you have an \(a\) which seems to have disappeared
\[5a-8a=-3a\] is better

Answer 10

so you should be looking at
\[-3a=0\]

Answer 11

ohhhh then 3a-8a =5-5=0

Answer 12

lets go slow

Answer 13

there is no 5 in it
it should be \[5a-8a=7-7\\
-3a=0\]

Answer 14

yea

Answer 15

and if \(-3a=0\) then of course \(a=0\)

Answer 16

well then what do you do with the 3

Answer 17

@satellite73

Answer 18

ok lets think
i have a number , i am not telling you what it is
but if you multiply it by -3 you get zero
what is my number?

Answer 19

0

Answer 20

done

Answer 21

thanks. :)

Answer 22

in other words, if
\(-3a=0\) then \(a=0\)
yw