$x,\ y-numbers\\\\\text{The system of equations:}\\\\\underline{+\left\{\begin{array}{ccc}x+y=126\\x-y=42\end{array}\right}\qquad\text{add both sides of the equations}\\.\qquad2x=168\qquad\text{divide both sides by 2}\\.\qquad x=84\\\\\\\text{Put the value of}\ x\ \text{to the first equation:}\\\\84+y=126\qquad\text{subtract 84 from both sides}\\y=42$

8 0

3 years ago

Which shows the expression x^2-1/x^2-x in simplest form

____ [38]

Answer:

$\large\boxed{\dfrac{x+1}{x}=1+\dfrac{1}{x}}$

Step-by-step explanation:

$\dfrac{x^2-1}{x^2-x}=(*)\\\\x^2-1=x^2-1^2\qquad\text{use}\ a^2-b^2=(a-b)(a+b)\\=(x-1)(x+1)\\\\x^2-x=(x)(x)-(x)(1)\qquad\text{use the distributive property}\\=x(x-1)\\\\(*)=\dfrac{(x-1)(x+1)}{x(x-1)}\qquad\text{cancel}\ (x-1)\\\\=\dfrac{x+1}{x}=\dfrac{x}{x}+\dfrac{1}{x}=1+\dfrac{1}{x}$

4 0

3 years ago

Read 2 more answers

Which characteristics best describe a right scalene triangle? I. Two sides meet at a 90° angle. II. Two side lengths are equal.

Alisiya [41]

Answer:

Step-by-step explanation:

8 0

3 years ago