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128bdubbz

Guest

Determinants

I could really use some help figuring out the answers to these problems!

Find the area of the parallelogram with the following vertices:

11. (-2, 3), (5, 8), (3, 3), and (0, 8)

12. (-2, 7), (-4, 4), (-11, 4), and (-9, 7)

13. (-6, 6), (-6, 3), (-12, 3), and (-12, 6)

14. (12, -3), (5, -6), (5, -3), and (12, -6)

15. (-2, 2), (-6, 9), (-13, 9), and (-9, 2)

Find the equation of the line that passes through the following points. Put your equation into slope-intercept form:

16.  (4, 25), (8, 61)

17. (-8, -1), (0, -1)

18. (3, -41), (1, -9)

19. (-6, -70), (4, 50)

20. (9, -98), (0, 19)

Monox D. I-Fly

Member

From: Indonesia

Registered: 2015-12-02

Posts: 2,000

Re: Determinants

For number 11-15, you could just draw them in coordinates then use the usual area formula.

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iamaditya

Member

From: Planet Mars

Registered: 2016-11-15

Posts: 821

Re: Determinants

Hi;

Visiting this forum after quite a long time, due to my internet connection. Hope everything has gone on fine when I was not here.

For your question, to solve questions 16 to 20, you can either use the formula method or the substitution method. I have given below the detail.

If a line passes through the points

then there are two methods to solve it. They are

1. Formula Method:

There is a direct formula that gives the equation of a line. It is

You can directly put the variables here and get the equation. For example in your sixteenth question, the equation would be

2. The substitution method

You can jot the 2 values of x and y you got into 2 equations of the form y=mx+c and then solve them simultaneously. For example in your sixteenth question, the equation would be

So, we can then get c=-11.

Hope it helps. For more info visit the Coordinates topics in mathsisfun.

Last edited by iamaditya (2017-06-08 22:12:52)

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