if line ax+ 3y=7 and (a-1)x+2y=b are perpendicular then sum of square of A
Answers
Answer:
Given:-
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in a text (+5) mark are given for every correct ans and (-2) mark are given for every incorrect ans. Rahul answered all the questions and scored 40 marks though he got 16 incorrect ans.
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To Find:-
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How many incorrect ans had he attempt
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STEP BY STEP EXPLANATION:-
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\implies⟹ Marks Has given for correct answer = 5
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\implies⟹ Marks deducted for incorrect = 2
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\implies⟹ Marks obtained by rahul = 40
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\implies⟹ No of correct answer by rahul = \sf \frac{40}{2} = 20
2
40
=20
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Answer:-
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\therefore∴ 20 incorrect answer has given by rahul
Please mark me as a brainliest
If θ is the angle made by a line with positive direction of x-axis in anticlockwise direction,
then the value of tan θ is called the slope of the line and is denoted by m.
The slope of a line passing through points P(x
1
, y
1
) and Q (x
2
, y
2
) is given by
2 1
2 1
tan
y y
m
x x
−
= θ =
−
10.1.2 Angle between two lines The angle θ between the two lines having slopes m1
and
m2
is given by
1 2
1 2
( )
tan
1
m m
m m
−
θ= ±
+
If we take the acute angle between two lines, then tan θ =
1 2
1 2 1
m m
m m
−
+
If the lines are parallel, then m1
= m2
.
If the lines are perpendicular, then m1m2 = – 1.
10.1.3 Collinearity of three points If three points P (h, k), Q (x
1
, y
1
) and R (x
2
,y
2
)
are such that slope of PQ = slope of QR, i.e., 1 2 1
1 2 1