Help? Math Q

[Pen Marks]

Here's the question,

Geometry Find the area of a triangle whose vertices have coordinates
(3, 1), (-4, 1), and (3, 5).

so how do i find the area of a triangle if i don't have the lenght of the sides? :-[

This is for Algebra 1 btw

Jazakallah khair in advance

 

[barney]

Here's the question,



so how do i find the area of a triangle if i don't have the lenght of the sides? :-[

This is for Algebra 1 btw

Jazakallah khair in advance

Get the length of the sides by plotting the coordinates on graph paper, making a grid from -4 to +3 on the x axis and +1 to +5 on the Y axis?

 

[Pen Marks]

i graphed it then what?

 

[barney]

Umm, its half the baselength X perpedicular height.
My maths is really old!

 

[barney]

http://www.cimt.plymouth.ac.uk/projects/mepres/book7/bk7i9/bk7_9i5.htm

There ya go

 

[Pen Marks]

i know how to get the area of a triangle, but in this q, they don't give me the lenghts

 

[Orn]

A(3,1),B(-4,1)
AB(square)=({-4}-3)[square]+(1-1)[square] , I used this method to find the distance between the points and the apply the regular 1/2x(base)(height) to find the area

 

[Qadri]

your length is the distance between -4 and 3 ... which is 7

your height is the difference between 5 and 1 ... which is 4

so your area is (0.5x7) x 4 = 14

 

[The Ruler]

Length of a line with coordinates (x1, y1) and (x2, y2) = square root of [(x1-x2)^2+(y1-y2)^2]

So for example... (from your question)

length of line with coordinates (3,1) and (-4,1) = Square root of [(3+4)^2+(1-1)^2]
= sq root of [49+0]
= 7 units.

 

[Ali.]

i know how to get the area of a triangle, but in this q, they don't give me the lenghts

They give you the points and you have to work out the lengths from there.

I believe the answer is 14 units.

 

[Pen Marks]

ok thanks

how bout this one,

Write an expression containing three integers that has a value of zero. One integer should be inside absolute value symbols.

 

[Abdu-l-Majeed]

@ Muminah:

I just saw this, I think I could have helped inshaAllah, anyway, it can help you in future.

1. question:

If you know how to solve matrixes, you use this matrix:

Or, use this:

http://imageshack.us

2. question:

If I understood you right, this could be the solution:|-3| - 2 - 1The value of this expression is 0 and it contains 3 integers, one if them is in abs. brackets.