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Given that ABCD is a parallelogram and A(1,1,0) B(-1,-1,-1) C(2,2,0) then what are the co-ordinates of D ? Also find the area of parallelogram ABCD ?
A triangle has 2 sides of length 5 and 6. The triangle's area is 12 .What is the angle between these two sides ?
Given the points A=(1,0,1) and B(1,1,1) and C(1,6,a) determine : (a) For what values of z are the points collinear ? (b) Determine if value exists for a so that A, B, c are three vertices of a parallelogram of area 3. If the value exists determine the co-ordinates of C ?

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Comments

1. Find the mid point of AC (diagnol) and then apply section formula (here mid point formula) on BD as it is also the mid point of BD. Because in ||gm Diagnols bisect each other.

2.Area of triangle when two sides and angle contained between the sides are given is $\frac{1}{2}ABsin\theta$ A and B are the lengths of sides.

$\frac{1}{2}5.6sin\theta$ =12.

$sin\theta$ =4/5

$\theta$ =53 degrees

Gautam Sharma - 6 years, 7 months ago

3 one is lengthy thats why i m not writin that BUT 3 part is deeply same as 1 st part.

Gautam Sharma - 6 years, 7 months ago

Thanks !!

Gaurav Sharma - 6 years, 7 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$