Question

if y=-2/5x-1/5 and y=3/2x-27/2, then what is solution?

(7, 3)

(-7, 3)

(7, -3)

(-7, -3)

Answer 1

(7, -3)

Answer 2

we do not like fractions when solving simultaneous eqn...
\(y=-\frac{2}{5}x-\frac{1}{5}\)---> multiply the eqn by 5
\(y=-\frac{3}{2}x-\frac{27}{2}\)--->multiply the eqn by 2
\(5y=-2x-1\)
\(2y=-3x-27\)
\(5y+2x=-1\)-->First eqn
\(2y+3x=-27\)--> Second eqn
Now,i'm using elimination method...
Let's say we want to eliminate y,we must make both coefficient of the eqn the same...
\(5y+2x=-1\)--> multiply the eqn by 2
\(2y+3x=-27\)-->multiply the eqn by 5
Both the eqns will look like this...
\(10y+4x=-2\)
\(10y+15x=-27\)

Answer 3

\(\color{red}{10y}+4x=-2\)
\(\color{red}{10y}-15x=-135\)

Answer 4

since,both hv the same coefficient in each eqn...
now,it is easier to eliminate y...

Answer 5

\(19x=133\)
divide both sides by 19

Answer 6

u will get \(x=7\)

Answer 7

substitute x=7 into the first eqn.

Answer 8

\(5y+2x=-1\)

Answer 9

\(5y+2(7)=-1\)
\(5y+14=-1\)

Answer 10

subtract both sides by 14.

Answer 11

\(5y=-14-1\)
\(5y=-15\)

Answer 12

Lastly,divide both sides by 5

Answer 13

\(x=\frac{-15}{5}\)

Answer 14

simplify it...
\(x=\frac{-3\times5}{1\times5}\)
\(x=\frac{-3}{1}\times\frac{5}{5}\)
\(x=?\)

Answer 15

That's a lot of math that looks suspiciously like a calculator, but does it answer my multiple choice question?

Answer 16

Yes,it does... @JustSaiyan

Answer 17

yeah its (7, -3)

Answer 18

yep,@Hanna is right! ^

Answer 19

That was a lot of work. you could have just said that.

Answer 20

But I get it. You wanna get your smart score up.

Answer 21

i wanna u to understand better... ^
if i wanna get my smart score up,i could be at 100 already by just asking more question n spamming... xD

Answer 22

want u*

Answer 23

Lol thats how I got here. I asked history questions, lol