Respuesta :


Consider the equation y=f(x), with solutions of the form (x,y)


y=f(x) means that y equals an expression in terms of x, 

for example f(x) could be [tex] -5x^{2}+7x-1 [/tex], or [tex] 8\sqrt{x}- \frac{7}{x} [/tex]

so f(x) is an expression with x'es and numbers


Given 2 equations: 

i) y=f(x)       and     g) y=g(x)

the solutions of the system:

i.  y=f(x)   
ii. y=g(x)

are pairs (x,y) which satisfy both i and ii, at the same time.

to solve this system, we let f(x)=g(x).


In our problem, we are given: [tex] \frac{1}{3}(x-2)= \frac{1}{4}(x+11) [/tex]

since both expressions are expressions of x and some numbers, 

let 

[tex]f(x)=\frac{1}{3}(x-2)[/tex]   and    [tex]g(x)=\frac{1}{4}(x+11)[/tex]

then a system of equations is:

i)  [tex]y=\frac{1}{3}(x-2)[/tex]
ii) [tex]y=\frac{1}{4}(x+11)[/tex]


Remark:

to find the solutions:

[tex]\frac{1}{3}(x-2)= \frac{1}{4}(x+11)[/tex]

4(x-2)=3(x+11)

4x-8=3x+33

x=33+8=41

to find y substitute x=41 in either of the equations:

for x=41, y=1/3 (x-2) = 1/3 (41-2) =1/3 (39) = 13

[or y= 1/4 (x+11) = 1/4 (41+11)= 1/4 (52) = 13