Sign In
What criteria need to be met for a quadrilateral to be a rectangle?
x^(∘)=100^(∘)
y^(∘)=50^(∘)
z^(∘)=40^(∘)
Let's take a look at the given figure. Notice that the quadrilateral has two pairs of parallel sides and one right angle.
Also notice that in a rectangle, the bisecting diagonals divide it into four isosceles triangles. Therefore, if we consider the lower triangle with one of the angle measures equal to y^(∘), the other base angle measure is also y^(∘).
The remaining angle is vertical to the 80^(∘) angle, so the two angles are congruent.
Add terms
LHS-80^(∘)=RHS-80^(∘)
.LHS /2.=.RHS /2.
Angle z^(∘) and 50^(∘) are complementary, meaning that their measures add up to 90^(∘). z^(∘)+50^(∘)=90^(∘) ⇔ z^(∘)=40^(∘) Now that we have found the value of z^(∘), we can summarize our findings. We found that x^(∘)=100^(∘), y^(∘)=50^(∘), and z^(∘)=40^(∘).