Solve the system using any method.
1)3x+5y=-1
2x-y=-5

Question

Solve the system using any method.
1)3x+5y=-1	
2x-y=-5

amistre64 · Answer

any method?

anonymous · Answer

substion

amistre64 · Answer

x   y
3  5 = -1	
2 -1 =-5

y = (-15+2)/(-3-10)

x = (-25+1)/(10+3)

anonymous · Answer

spell wrong sorry

anonymous · Answer

so whats y and whats x

amistre64 · Answer

well, when you have just numbers, you tend to work thru the math like they did back in kindergarten :)

y = (-15+2)/(-3-10)
   = -13/-13
   =1

x = (-25-1)/(10+3)
   = -26/13
   =-2

anonymous · Answer

y =1 and x=-2

amistre64 · Answer

yep; that method is known as cramers method, i figured it out before i know that there was a method for it ....

anonymous · Answer

okay thanks so thats works as the subsatotion method also

amistre64 · Answer

yes; it tends to be the quickest method since it just follows a pattern that pulls the numbers out rather then alot of mental mathematical gymnastics

anonymous · Answer

okay thanks do you think you couldl help me with a different problem

anonymous · Answer

Tell whether this given ordered triple is a solution of a system.
(3,3,4)
X+2y-2z=1
7x-4y+z=11
2x-3y+2z=5

amistre64 · Answer

given 2 equations: ax + by = n  and  cx + dy = m
\begin{array}c
a&b&n\
c&d&m\\\end{array}$$y=\frac{ma-nc}{ad-bc}$$$$x=\frac{mb-nd}{bc-ad}$$

amistre64 · Answer

the only way to tell is to plug them in to see

amistre64 · Answer

25
-12
-----
  13 not 11

anonymous · Answer

i am lost

anonymous · Answer

so no its not a solution

amistre64 · Answer

it dont fit the 2nd equation, so it cant be a solution