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Identify the x-intercepts for y = 3(x + 4)2 - 5. Choose all correct answers.No solutionOx= -5.291x = -3.225x = -2.709Question 6 (1 point)✓ Saved

User Damir Porobic
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1 Answer

19 votes
19 votes

kyliehamilton0022, this is the solution:

y = 3(x + 4)² - 5

Let's find the x-intercept, this way:

y = 0

Thus:

0 = 3(x + 4)² - 5

0 = 3(x² + 8x + 16) - 5

3x² + 24x + 48 - 5 = 0

3x² + 24x + 43 = 0

Using the quadratic equation, we have:

x = - 24 +/- (√24² - 4 * 3 * 43)/2 * 3

x = - 24 +/- (√576 - 516)/6

x = - 24 +/- √60/6

x = - 24 +/- 2√15/6

Dividing by 2 numerator and denominator:

x = (- 12 +/- √15)/ 3

Let's find the roots for solving for x

x = - 12+/- 3.8729/3

x1 = - 15.8729/3 = -5.2991

x2 = - 8.1271/3 = -2.709

Therefore, the correct answers are B and D

User Nikolay Mihaylov
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