Answer:45
Step-by-step explanation:
The
first choice gives you the same result. The factor of 5 can be removed to the outside of the summation symbol.
Since AB = CD the trapezoid is isosceles, which means that ∡A = ∡D
Therefore also ∡2 = ∡3 (they are half of the congruent angles)
For the properties of parallel lines (BD and AD) crossed by a transversal (BD) we have ∡3 = ∡CBD.
Now consider triangles AOD and BCD:
∡OAD (2) = ∡ADO (3) = ∡CBD (3) = ∡CDB (4)
T<span>he sum of the angles of a triangle must be 180°, t</span>herefore:
∡AOD = 180 - ∡2 - ∡3
∡BCD = 180 - ∡3 - ∡4
∡AOD = ∡BCD because their measure is the difference of congruent angles.
Answer:
17.5 in
Step-by-step explanation:
Step one:
given
The perimeter of a rectangle is 53 inches
let the two shorter sides be the width w
so w+w= 18in
the two longer sides is L
L+L=2l
Step two:
but the expression for the perimeter of a rectangle is
P=2W+2L
53= 18+2L
53-18=2L
35=2L
divide both sides by 1
L=35/2
L=17.5
Answer:
10.01929292919191919199119919191919191911