If a=9- 4(5)^1/2, then what is the value of a?

Given, a = 9 - 4/(5)^1/2

or, a = 9 - 4/2.23606 = 9 - 1.78885... = 7.2111.

Generally 3 figures after the decimal are taken into account. .(Ans)

HE

N

a=9-4(5)^¹/₂

a=9-4(5)/2

a=9-20/2

a=9-10

a=-1 #

-1

sqrt5-2

You really should add any updates directly to the question so that everyone can see it. When you add an update as an answer to your question, most people are likely to miss it.

Also, when you say "that's a^(1/2)", which a are you referring to?

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If a^(1/2) = 9 − 4√5, then what is the value of a?

a^(1/2) = 9 − 4√5

a = (9 − 4√5)²

a = (9 − 4√5) (9 − 4√5)

a = 9 (9 − 4√5) − 4√5 (9 − 4√5)

a = 81 − 36√5 − 36√5 + 80

a = 161 − 72√5

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If a = 9 − 4√5, then what is the value of a^(1/2)?

a = 9 − 4√5

a = 4 − 4√5 + 5

a = 2² − 2(2√5) + (√5)²

a = (2 − √5)²

a^(1/2) = √((2 − √5)²) = |2 − √5| = √5 − 2

What you wrote was a to the first power, divided by 2.

If you mean a to the 1/2 power, then you need parenthesis, so if you really mean:

a = 9 - 4(5)^(1/2)

Then the 1/2 power becomes the square root:

a = 9 - 4√5

And that's the simplified exact answer. If you need a decimal approximation, then we can use a calculator to get :

a = 9 - 4 * 2.2361 (rounded to 4DP here, but didn't round in my calculator to reduce rounding errors)

a = 9 - 8.9443 (same with this step)

a = 0.0557 (and here I'll leave it rounded to 4 DP).

Assuming you mean 9- 4*(5)^(1/2)

the value is approximately .05572809

9-4(5)^1/2 = 9-4(5)/2 = 9-20/2 = 9-10 = -1