SOLUTION: Give exact and aproximate solutions to y^2-10y+25=49

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Question 553738: Give exact and aproximate solutions to y^2-10y+25=49
Found 2 solutions by Earlsdon, josmiceli:
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Solve:
y%5E2-10y%2B25+=+49 Subtract 49 from both sides.
y%5E2-10y-24+=+0 Factor.
%28y%2B2%29%28y-12%29+=+0 Apply the zero product rule.
y%2B2+=+0 or y-12+=+0 so...
y+=+-2 or y+=+12

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Both sides are perfect squares
+y%5E2+-+10y+%2B+25+=+49+
+%28+y+-+5+%29%5E2+=+7%5E2+
Take square root of both sides
+y+-+5+=+7+
+y+=+12+
and also
+y+-+5+=+-7+
+y+=+-2+
check answers:
+12%5E2+-+10%2A12+%2B+25+=+49+
+144+-+120+%2B+25+=+49+
+24+%2B+25+=+49+
+49+=+49+
OK
+%28-2%29%5E2+-+10%2A%28-2%29+%2B+25+=+49+
+4+%2B+20+%2B+25+=+49+
+49+=+49+
OK