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3 years ago

The perimeter of a rectangle is 42 inches. If the width of the rectangle is 6 inches, what is the length?

Mathematics

2 answers:

Andrews [41]3 years ago

4 0

Answer:

B. 15 inches.

Step-by-step explanation:

A rectangle shares two pairs of congruent opposite sides.

Perimeter = 42

Let:

the length of the rectangle = l

the width of the rectangle = w = 6

Perimeter = l + l + w + w

Plug in 42 for perimeter & 6 for w in the equation:

42 = l + l + 6 + 6

Combine like terms:

42 = ( l + l ) + (6 + 6)

42 = 2l + 12

Next, isolate the variable, l. Do the opposite of PEMDAS. First, subtract 12 from both sides:

42 (-12) = 2l + 12 (-12)

42 - 12 = 2l

30 = 2l

Next, divide 2 from both sides:

(30)/2 = (2l)/2

l = 30/2

l = 15

B. 15 inches is the length of the rectangle.

Check:

l + l + w + w = 42

15 + 15 + 6 + 6 = 42

30 + 12 = 42

42 = 42 (True).

Stella [2.4K]3 years ago

3 0

Answer:

b.15 inches

Step-by-step explanation:

subtract 12 (2 6inch sides) from the perimeter

get 30 and divide by 2 to get 2 sides

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To evaluate, substitute 3 for x in the expression, and then simplify.

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To evaluate the expression when x=1, we substitute 1 for x, and then simplify.

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3 years ago

Which statement best completes the sentence below? If the measure of /_4 is 70^o, then the measure of /_8 is _________________.

Alex_Xolod [135]

Answer:

As given, measure of angle 4 is 70°

Then what would be the measure of ∠8.

Following cases comes into consideration

1. If ∠4 and ∠8 are supplementary angles i.e lie on same side of Transversal, then

∠4 + ∠8=180°

⇒70°+∠8=180° [∠4=70°]

⇒∠8=180°-70°

⇒∠8=110°

2nd possibility

But if these two angles i.e ∠4 and ∠8 forms a linear pair.Then

⇒ ∠4 + ∠8=180°

⇒70°+∠8=180° [∠4=70°]

⇒∠8=180°-70°

⇒∠8=110°

3rd possibility

If ∠4 and ∠8 are alternate exterior angles.

then, ∠4 = ∠8=70°

4th possibility

If If ∠4 and ∠8 are corresponding angles.

then, ∠4 = ∠8=70°

Out of four options given Option A[ 110° because ∠4 and ∠8 are supplementary angles], Option B[70° because ∠4 and ∠8 are alternate exterior angles.] and Option D[70° because ∠4 and ∠8 are corresponding angles.] are Correct.