Answer:


Step-by-step explanation:
Given system of equations:

To solve by the method of substitution, substitute the first equation into the second equation and rearrange so that the equation equals zero:

Factor the quadratic:

Apply the <u>zero-product property</u> and solve for x:


Substitute the found values of x into the <u>second equation</u> and solve for y:


Therefore, the solutions are:


<span>$21 times .06 = $1.26 in taxes and $21 times .15 = $3.15 in tip so you add $21+ 1.26 + 3.15 = $25.41
</span>
Plug in 6 for x and solve out for f(x)
Answer:
20%=8
10%=?
by cross multiplications,
10×8=80
80÷20=4
Hence the answer is 4.