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4 votes
Solve 5x^2 - 3x = 7 using the quadratic formula.

Help on the last step few steps, after 3±√149 / 10

User Raffel
by
5.6k points

1 Answer

4 votes

Answer:

x = 2.3 and x = 3.7

Explanation:

For an equation "ax2 + bx + c = 0", the values of x which are the solutions of the equation are given by the quadratic formula as

x = -b ± √(b² − 4ac) / 2a

Given in the question that

5x² - 3x = 7

5x² - 3x - 7 = 0

a = 5

b = -3

c = -7

Put these value in quadratic equation

x = -b ± √(b² − 4ac) / 2a

x = -(-3)± √((-3)² - 4(5)(-7) ) / 2(5)

x = 3 ± √(9 - 4(5)(-7) ) / 10

x = 3 ± √(9 + 140 ) / 10

x = 3 ± √(9 + 140 ) / 10

x = 3 ± √(149 ) / 10

x = 3 ± 7 / 10

x = 3 - ( 7 / 10 ) and x = 3 + 7 / 10

x = 23/10 and x = 37/10

x = 2.3 and x = 3.7

User Pankaj Bisht
by
5.2k points
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