0.7x^2=4.2x+0.7
The answers I'm getting are some reallllly big decimals so I don't think I'm doing it right. Help please?
The answers I'm getting are some reallllly big decimals so I don't think I'm doing it right. Help please?
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Rearrange the terms to get:
0.7x² - 4.2x - 0.7 = 0
Note that we can factor that expression by 0.7 to get:
0.7(x² - 6x - 1) = 0
Here, by ax² + bx + c = 0, neglecting 0.7, a = 1, b = -6 and c = -1. Then, by quadratic formula:
x = (-b ± √(b² - 4ac))/2a
= (6 ± √((-6)² - 4*1*-1))/2
= (6 ± √(36 + 4))/2
= (6 ± √40)/2
= (6 ± √(4*10))/2
= (6 ± 2√10)/2
= 2(3 ± √10)/2
= 3 ± √10
I hope this helps!
0.7x² - 4.2x - 0.7 = 0
Note that we can factor that expression by 0.7 to get:
0.7(x² - 6x - 1) = 0
Here, by ax² + bx + c = 0, neglecting 0.7, a = 1, b = -6 and c = -1. Then, by quadratic formula:
x = (-b ± √(b² - 4ac))/2a
= (6 ± √((-6)² - 4*1*-1))/2
= (6 ± √(36 + 4))/2
= (6 ± √40)/2
= (6 ± √(4*10))/2
= (6 ± 2√10)/2
= 2(3 ± √10)/2
= 3 ± √10
I hope this helps!