Question

2a+4b=10
3a-b=1
Tell which equation you would
use to isolate a variable. Explain the reasoning

Answer 1

id recommend waiting for someone else's opinion, but,

i would use 3a-b=1 if you were given one of the two variables to solve the equation, it would be simpler to divide once rather then multiple times to solve the equation

for instance 3a-b=1 3a=b+1 a = (b+1)/3

the other formula 2a = 10 - 4b
divide by 2 and
a = 5 - 2b

*Still new and relearning take this only as a method to check your work*

Answer 2

I'd use the second one because it's more simple to isolate the b and you wouldn't have to divide by 10 and possibly end up with fractions.

3a-b=1
-b=-3a+1 ;minus 3a from both sides
b= 3a-1 ;multiply by -1 to make b positive
So b=3a-1

Now plug b into the first equation
remember b=3a-1.
So
2a+4(3a-1)=10
2a+12a-4=10 ;distribute 4
14a-4=10; combine like terms
14a=14; add 4 to both sides
a=1; divide both sides by 14
So a=1

Answer 3

thanks daydream you helped me as well, i knew you could "solve" these but its been years and i had forgotten the method

Answer 4

yeah that happens with math, easy to forget. but yeah no problem

Answer 5

thank you do much

Answer 6

soo

Answer 7

:) your welcome. keep trying, these become very simple