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2 years ago

Plz help on rationalising surds

Mathematics

1 answer:

Fittoniya [83]2 years ago

3 0

(√5 + 3)² / √20=
((√5 + 3)² / √20)(√20/√20)=
(√20(√5 + 3)²) / (√20)²=
√20(5+6√5+9) /20=
√20 (14+6√5) /20=
(14√20 +6√100) /20=
(14√20 +60) / 20=
(14(√4√5) + 60) /20=
(14(2)(√5)+60) / 20=
(28√5+60) /20=
(7√5+15) / 5

Answer:(√5 + 3)² / √20= <span>(7√5+15) / 5</span>

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Answer:

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Step-by-step explanation:

The slope-intercept form of a line is y=mx-b where m is slope and b is y-intercept.

The point-slope form of a line is y-y1=m(x-x1) where m is the slope and (x1,y1) is a point on the line.

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so the equation of our line in slope-intercept form is $y=\frac{3}{4}x+1$

So that isn't option 1 because the slope is different. That was the only option that was in slope-intercept form.

The standard form of a line is ax+by=c and we have 2 options that look like that.

So let's rearrange the line that we just found into that form.

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Clear the fractions because we only want integer coefficients by multiplying both sides by 4.

This gives us:

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Subtract 3x on both sides:

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I don't see this option either.

Multiply both sides by -1:

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I do see this as a option. So far the only option that works is 2.

Let's look at point slope form now.

We had the point that our line went through was (x1,y1)=(-4,-2) and the slope,m, was 3/4 (we found this earlier).

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Plug in like so:

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So option 5 looks good too.

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