Question

in the figure above, lines $ell$ and $m$ are parallel, $y = 20$, and $z = 60$. what is the value of $x$? a 120 b 100 c 90 d 80

Explanation:

Step1: Use property of parallel lines

Since lines $\ell$ and $m$ are parallel, we can find a related angle. Let's assume a trans - versal intersects the parallel lines.

Step2: Consider angle - sum property

We know that the sum of angles in a triangle - like situation (formed by the angles $x$, $y$, and $z$) is 180 degrees. So, $x + y+z=180$.

Step3: Substitute given values

Substitute $y = 20$ and $z = 60$ into the equation $x + y+z=180$. We get $x+20 + 60=180$.

Step4: Solve for x

$x=180-(20 + 60)=100$.

Answer:

B. 100