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Curriculum: Click to change Curriculum Topic: Click to change Topic Lesson: Click to change Lesson
Attempt following question by selecting a choice to answer.
f
What are the measures of ∠b, ∠c and ∠d, if ∠a = 90o in the figure?ee ffA. f90 o, 30 o and 60 oB. f40 o, 140 o and 40 oC. f90 o, 90 o and 90 oD. fNone of the above
f
B
Step 1: From the figure, 50o + ∠d = 90o.[50o and ∠d are complementary angles.]
Step 2: ∠d = 90o - 50o = 40o[Subtract 50o on both sides and simplify.]
Step 3: ∠d and ∠c, ∠c and ∠b form linear pairs.
Step 4: Sum of the angles forming linear pairs is 180o.
Step 5: ∠d + ∠c = 180o.
Step 6: 40o + ∠c = 180o[Substitute ∠d = 40o.]
Step 7: ∠c = 180o - 40o = 140o[Subtract 40o on both sides and simplify.]
Step 8: ∠c + ∠b =180o.
Step 9: 140o + ∠b = 180o[Substitute ∠c = 140o.]
Step 10: ∠b = 180o - 140o = 40o[Subtract 140o on both sides and simplify.]
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