Did you notice the little box with corners marked in the angle down at the bottom ?
That angle is a right angle, and <em>this triangle is a right triangle</em> !
This piece of information is a big help. It breaks the problem wide open.
You know that in order to find the longest side of a right triangle . . .
-- Square the length of one short side.
-- Square the length of the other short side.
-- Add the two squares together.
-- Take the square root of the sum.
One short side=48. Its square = 2,304.
The other short side=48. Its square = 2,304.
Add the two squares: 2,304 + 2,304 = 4,608
The square root of the sum = √4,608 = <em><u>67.88</u></em> (rounded)
We know that
• Lashonda purchased a prepaid phone card for $20.
,
• Long-distance calls cost 8 cents a minute.
,
• The remaining credit on her card is $17.12.
This problem can be expressed as
![20-0.08x=17.12](https://tex.z-dn.net/?f=20-0.08x%3D17.12)
Where <em>x</em> is the number of minutes.
We solve the equation for <em>x</em>
![\begin{gathered} -0.08x=17.12-20 \\ -0.08x=-2.88 \end{gathered}](https://tex.z-dn.net/?f=%5Cbegin%7Bgathered%7D%20-0.08x%3D17.12-20%20%5C%5C%20-0.08x%3D-2.88%20%5Cend%7Bgathered%7D)
Then, we divide by -0.08 the equation
![\begin{gathered} \frac{-0.08x}{-0.08}=\frac{-2.88}{-0.08} \\ x=36 \end{gathered}](https://tex.z-dn.net/?f=%5Cbegin%7Bgathered%7D%20%5Cfrac%7B-0.08x%7D%7B-0.08%7D%3D%5Cfrac%7B-2.88%7D%7B-0.08%7D%20%5C%5C%20x%3D36%20%5Cend%7Bgathered%7D)
<h2>Therefore, Lashonda's call last 36 minutes.</h2>
The equation of a line is:
y = mx + c
The m is the gradient of the line, and the c is the y-intercept of the line
That means that the y-intercept of [y = -4x + 3] is 3
and the y-intercept of [y = -4x + 4] is 4
So the distance between the two y-intercepts is:
4 - 3 = <u>1</u>
Liter is not equivalent to one of the metric units