Mathematics, 20.02.2021 20:20, arod20061

The coordinates of the vertices of △UVW are U(−2,−1), V(2,−1), and W(2,−8). Find the side lengths to the nearest hundredth and the angle measures to the nearest degree.

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answered: babygirl200702

UV = 4; VW = 7, UW ≈ 8.06

m∠V = 90°, m∠U ≈ 60°, m∠W ≈ 30°

Step-by-step explanation:

Using the distance formula, find the length of UW⎯⎯⎯⎯⎯⎯⎯.

UW=(2−(−2))2+(−8−(−1))2‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾√

Simplify.

UW=(4)2+(−7)2‾‾‾‾‾‾‾‾‾‾‾‾√

Square.

UW=16+49‾‾‾‾‾‾‾√

Simplify.

UW=65‾‾‾√

Use a calculator to approximate.

UW≈8.06

Therefore, UW≈8.06.

Using the distance formula, find the length of UV⎯⎯⎯⎯⎯⎯.

UV=(2−(−2))2+(−1−(−1))2‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾√

Simplify.

UV=(4)2+(0)2‾‾‾‾‾‾‾‾‾‾√

Square.

UV=16+0‾‾‾‾‾‾√

Simplify.

UV=16‾‾‾√

Simplify.

UV=4

Therefore, UV=4.

Using the distance formula, find the length of VW⎯⎯⎯⎯⎯⎯.

VW=(2−2)2+(−8−(−1))2‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾√

Simplify.

VW=(0)2+(−7)2‾‾‾‾‾‾‾‾‾‾‾‾√

Square.

VW=0+49‾‾‾‾‾‾√

Simplify.

VW=49‾‾‾√

Simplify.

VW=7

Therefore, VW=7.

The figure shows the same triangle U V W on a Cartesian plane as in the beginning of the task. The length of segment U V is 4 units. The length of segment V W is 7 units. The length of segment U W is 8.06 units.

Notice that UW2=UV2+VW2. So, by the Converse of the Pythagorean Theorem, △UVW is a right triangle.

Since VW⎯⎯⎯⎯⎯⎯ and UV⎯⎯⎯⎯⎯⎯ are perpendicular, m∠V=90°.

Therefore, m∠V=90°.

By the definition of tangent, tan∠U=VWUV.

Take the inverse tangent of both sides.

m∠U=tan−1(VWUV)

Substitute 7 for VW and 4 for UV.

m∠U=tan−1(74)

Use a calculator to calculate the inverse tangent.

The figure shows a calculator screen on which the inverse tangent of seven fourths is calculated. The result of the calculation is 60 point 2 5 5 1 1 8 7.

m∠U≈60°

Therefore, m∠U≈60°.

The figure shows the same triangle U V W on a Cartesian plane as in the beginning of the task. Angle V is a right angle. Angle U measures 60 degrees.

The acute angles of a right triangle are complementary by the corollary of the Triangle Sum Theorem.

So, m∠U+m∠W=90°.

Substitute 60° for m∠U.

60°+m∠W≈90°

Subtract 60° from both sides.

m∠W≈90°−60°

Simplify.

m∠W≈30°

Therefore, m∠W≈30°.