Question

pls help last 3 problems!!!!
thanks!!!! :)))

Answer 1

for number 2, you just need to look at where the two lines intersect. in this case, they intersect at (2, 1)

Answer 2

and then, i plugged in those numbers into each equation to be sure the math worked out and it did.

Answer 3

for number 1...just use simultaneous eqs.

and subract the 2y to get---> 8x = -16

which gives you x = -2

since theres only one option with that value...thats the first one (-2,3)

Answer 4

but im stuck on the last one though...

using simultaneous eq's... you could multiply the bottom one by -3 to get rid of the y terms

but theres a problem

\[3x -9y = 0\]
\[ [(-x +3y = -3)\times-3] = [-3x - 9y = -9]\]

so if you subtract those 2 equations to try and get rid of one term...you get rid of them both....

so you end up with 0 = 9

which i would say is 0 no. of solutions...