can you help me with math please.

Question

Find the area of the triangle formed by the coordinate axes and the line
2y + 5x − 10 = 0.

Answer 1

The easiest way to answer this question is to get the equation into standard format (y=mx+b)

 

So let's do some algebra:

2y + 5x - 10 = 0

-2y                  -2y

----------------------

5x-10 = -2y

or

-2y = 5x - 10

 

Now you'd like to know where on the axes your line hits. So where does x=0 and where does y=0?

 

5(0)-10=-2y

-10 = -2y

5=y

(0,2)

 

5x-10=-2(0)

5x-10=0

5x=10

x=2

(2,0)

 

Now you know that this is a right triangle that extends 2 units up the y axis and 2 units out to the right on the x axis.

 

The area of a triangle can be found using the formula A=1/2bh where b is the base and h is the height.

In this case, both are = 2.

So A = 1/2(2)(2) = 1/2 * 4 = 2 square units

 

Hope this helps!

Answer 2

Agreed, except the value of y when x=0 is 5. You wrote it as the result of the math: 5=y, but then you gave coordinates (0,2) instead of (0,5).

A=1/2(5)(2)=5 sqr units.

 

Am I right?