SOLUTION: Question Part Points Submissions Used Use the quadratic formula to find any x-intercepts of the parabola. (If an answer does not exist, enter DNE.) y = 2x^2 − 10x + 5

Algebra ->  Quadratic-relations-and-conic-sections -> SOLUTION: Question Part Points Submissions Used Use the quadratic formula to find any x-intercepts of the parabola. (If an answer does not exist, enter DNE.) y = 2x^2 − 10x + 5      Log On


   

Question 988025: Question Part
Points
Submissions Used
Use the quadratic formula to find any x-intercepts of the parabola. (If an answer does not exist, enter DNE.)
y = 2x^2 − 10x + 5
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
At the x-intercepts, +y+=+0+, so
+2x%5E2+-+10x+%2B+5+=+0+
Use the quadratic formula
+x+=+%28+-b+%2B-+sqrt%28+b%5E2+-+4%2Aa%2Ac+%29%29+%2F+%282%2Aa%29+
+a+=+2+
+b+=+-10+
+c+=+5+
+x+=+%28+-%28-10%29+%2B-+sqrt%28+%28-10%29%5E2+-+4%2A2%2A5+%29%29+%2F+%282%2A2%29+
+x+=+%28+10+%2B-+sqrt%28+100+-+40+%29%29+%2F+4+
+x+=+%28+10+%2B-+sqrt%28+60+%29%29+%2F+4+
+x+=++5%2F2+%2B-+sqrt%2815+%29%2F2+
----------------------------
Check answers:
+x+=+2.5+%2B+3.873%2F2+
+x+=+2.5+%2B+1.936+
+x+=+4.436+
and
+x+=+2.5+-+3.873%2F2+
+x+=+2.5+-+1.936+
+x+=+.564+
------------------------
+2%2A4.436%5E2+-+10%2A4.436+%2B+5+=+0+
+2%2A19.678+-+44.36+%2B+5+=+0+
+39.356+-+44.36+%2B+5+=+o+
+-5.004+%2B+5+=+0+
close enough- you can check the other x-intercept