SOLUTION: 49x^2 -25=0 Find all the roots and check your answer

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Question 421036: 49x^2 -25=0
Find all the roots and check your answer
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+49x%5E2+-+25+=+0+
+49x%5E2+=+25+
+%287x%29%5E2+=+5%5E2
Take the square root of both sides
+7x+=+5+
x+=+5%2F7
and, taking the negative square root of 5%5E2
7x+=+-5
x+=+-5%2F7
The roots are 5/7 and -5/7
check answer:
x+=+5%2F7
+x+-+5%2F7+=+0+
and
x+=+-5%2F7
+x+%2B+5%2F7+=+0+
+%28x+-+5%2F7%29%2A%28+x+%2B+5%2F7%29+=+0+
+x%5E2+-+25%2F49+=+0+
x%5E2+=+25%2F49
+49x%5E2+=+25+
OK