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## lornbeach Group Title Simplify the given expression: one year ago one year ago

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1. lornbeach

2. maym0Re97

i7/1+9i

3. lornbeach

thats not an answer choice

4. maym0Re97

What are the choices?

5. lornbeach

7+7i/2 63+7i/82 -7+7i/2 -63+7i/82

6. Hero

$\sqrt{-49} = \sqrt{49 \dot\ -1} = \sqrt{49} \sqrt{-1} = 7i \$$3 + 4i) - (2 - 5i) = (3 - 2) + (4i + 5i) = 1 + 9i$ 7. Hero I have to agree with @maym0Re97 8. maym0Re97 Lol that's what I got, but it's not an answer choice 9. lornbeach i got that answer as well, but it isnt a choice 10. Hero There's probably an equivalent choice 11. Hero Multiply top and bottom by 1 - 9i and see what happens 12. lornbeach would it be 63+7i/82? 13. satellite73 your job is to rewrite in standard form as \(a+bi$$ which means do what @hero said

14. satellite73

$\frac{7i}{1+9i}\times \frac{1-9i}{1-9i}$ the denominator is $$1^2+9^2=82$$ all the work is in the numerator

15. satellite73

yes you have it

16. lornbeach

thank you(: