SOLUTION: what are the x-intercepts of the equation y=2x^2+4x-3 please answer with square roots or fractions

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Question 4465: what are the x-intercepts of the equation y=2x^2+4x-3
please answer with square roots or fractions
Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
The x-intercept simply means that y = 0. You must let y= 0 and solve for x:
y+=+2x%5E2+%2B+4x+-+3+
0+=+2x%5E2+%2B+4x+-+3+

Use the quadratic formula x+=+%28-b%2B-sqrt+%28b%5E2+-+4ac%29%29%2F%282a%29+, where a=2, b=4, and c=-3.

x+=+%28-4%2B-sqrt+%284%5E2+-+4%2A2%2A%28-3%29%29%29%2F%282%2A2%29+
x+=+%28-4%2B-sqrt+%2816+%2B+24%29%29%2F%284%29+
x+=+%28-4%2B-sqrt+%2840%29%29%2F%284%29+
x+=+%28-4%2B-sqrt+%284%29+%2Asqrt+%2810%29%29%2F%284%29+
x+=+%28-4%2B-2sqrt+%2810%29%29%2F%284%29+

Factor out the 2 factor in the numerator, and reduce the fraction:
x+=+%282%2A%28-2%2B-sqrt+%2810%29%29%29%2F%284%29+
x+=+%28-2%2B-sqrt+%2810%29%29%2F%282%29+

R^2 at SCC