For any quadrilateral to be a parallelogram
i) either both the pairs of opposite sides must be equal
ii) Both the pairs of opposite sides must be parallel
iii) Opposite pairs of angles must be equal
iv) Diagonals must bisect each other.
v) A pair of opposite sides must be parallel and equal
Here we are already given that AB || CD
So either we should be given that AD || BC
or we must be given that AB = CD
Here it is given AB = CD as an option.
So Option A) or the first option is the right answer that AB ≅CD is needed to prove ABCD is a parallelogram.
Answer:
B. 3 3/4
Step-by-step explanation:
3/8 * 10 = 30/8
30/8 = 3 3/4
If my math is right it should be b
11. m ∠ BCE = 25 °
m ∠BAD = 39°
12. n = 11. 5°
13. The quadrilaterals are rectangle and parallelogram. Option A and C
14. HK = 8cm
<h3>How to determine the angles</h3>
11. From the figure shown, we have that;
m ∠ EBC = 27°
m ∠ ADE = 52°
To find
m ∠ BCE
Note that m ∠ ADE is alternate and equal to m∠ DEC = 52 and is also on a straight line with ∠BEC
52 + ∠BEC = 180°
∠BEC = 180 - 52° = 128°
Remember that ∠BEC, ∠ BCE and ∠ EBC are angles in a triangle which sum up to 180°
128° + ∠ BCE + 27° = 180°
∠ BCE = 180 ° - 155°
∠ BCE = 25 °
To determine m ∠BAD
65° + 76 + m ∠BAD = 180° , sum of angles in a a triangle
m ∠BAD = 180 - 141
m ∠BAD = 39°
12. Value of n is gotten by equating the two lengths
( 10n + 19) = (12n - 4)
collect like terms
10n - 12n = -4 - 19
- 2n = -23
n = -23/-2
n = 11. 5°
13. The only quadrilaterals with congruent diagonals are;
14. To find line HK
Substract the shortest line, IJ from the longest line GL
HK = GL - IJ
HK = 15 - 7
HK = 8cm
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