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27 votes
27 votes
Solve the equation 25z2 + 140 = −29 by using square roots.

User Mohammed Sadiq
by
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2 Answers

25 votes
25 votes

Answer:

13i/5

Explanation:

25z^2+140=-29 subtract 140 from both sides

25z^2=-169 now square root both sides.


\sqrt{25z^(2) }=
√(-169) a negative root forms i

5z=13i

z=13i/5

User The Integrator
by
3.0k points
27 votes
27 votes

Answer:

z is 13i/5

Explanation:


{ \sf{25 {z}^(2) + 140 = - 29}} \\ { \sf{25 {z}^(2) = - 169 }} \\ { \sf{ \sqrt{25 {z}^(2) } = √( - 169) }} \\ { \sf{5z = √(169 * - 1) }} \\ { \sf{5z = √(169) * √( - 1) }} \\ { \sf{5z = 13 * \sqrt{ {i}^(2) } }} \\ { \sf{5z = 13i}} \\ { \sf{z = (13i)/(5) }}

User Mirzhan Irkegulov
by
3.1k points