document.write( "Question 1080078: How do you find real numbers a,b and c so that the graph of the function \"+y=ax%5E2%2Bbx%2Bc+\" contains the points (-1,5), (3,8) and (0,2)?\r
\n" ); document.write( "\n" ); document.write( "My process went as\r
\n" ); document.write( "\n" ); document.write( " (-1,5) is a point on the graph then values are, x=-1 and y=5 that must satisfy y=ax^2+bx+c
\n" ); document.write( "Equation one being \"+a%28-1%29%5E2%2Bb%28-1%29%2Bc=5+\"\r
\n" ); document.write( "\n" ); document.write( " (3,8) is a point on the graph then values are, x=3 and y=8 that must satisfy y=ax^2+bx+c
\n" ); document.write( "Equation two being \"+a%283%29%5E2%2Bb%283%29%2Bc=8+\"\r
\n" ); document.write( "\n" ); document.write( " (0,2) is a point on the graph then values are, x=0 and y=2 that must satisfy y=ax^2+bx+c
\n" ); document.write( "Equation three being \"+a%280%29%5E2%2Bb%280%29%2Bc=2+\"\r
\n" ); document.write( "\n" ); document.write( "that gives the system of 3 equation which are
\n" ); document.write( "ONE \"+a-b%2Bc=5+\"
\n" ); document.write( "TWO \"+9a%2B3b%2Bc=8\"
\n" ); document.write( "THREE \"+c=2+\"\r
\n" ); document.write( "\n" ); document.write( "then you start with ONE and THREE
\n" ); document.write( "\"+a%5E2-b%2Bc=5+\"
\n" ); document.write( "\"+c=2+\" < multiply each side by -1
\n" ); document.write( "and add to get a-b=3\r
\n" ); document.write( "\n" ); document.write( "Im not sure if thats the way to go where you then use equation 3 to eliminate c from equation 2 or if there's another process to get solutions of a, b and c? I'm thankful for any advice on this problem!
\n" ); document.write( "

Algebra.Com's Answer #694322 by MathTherapy(10555)\"\" \"About 
You can put this solution on YOUR website!

\n" ); document.write( "How do you find real numbers a,b and c so that the graph of the function \"+y=ax%5E2%2Bbx%2Bc+\" contains the points (-1,5), (3,8) and (0,2)?\r
\n" ); document.write( "\n" ); document.write( "My process went as\r
\n" ); document.write( "\n" ); document.write( " (-1,5) is a point on the graph then values are, x=-1 and y=5 that must satisfy y=ax^2+bx+c
\n" ); document.write( "Equation one being \"+a%28-1%29%5E2%2Bb%28-1%29%2Bc=5+\"\r
\n" ); document.write( "\n" ); document.write( " (3,8) is a point on the graph then values are, x=3 and y=8 that must satisfy y=ax^2+bx+c
\n" ); document.write( "Equation two being \"+a%283%29%5E2%2Bb%283%29%2Bc=8+\"\r
\n" ); document.write( "\n" ); document.write( " (0,2) is a point on the graph then values are, x=0 and y=2 that must satisfy y=ax^2+bx+c
\n" ); document.write( "Equation three being \"+a%280%29%5E2%2Bb%280%29%2Bc=2+\"\r
\n" ); document.write( "\n" ); document.write( "that gives the system of 3 equation which are
\n" ); document.write( "ONE \"+a-b%2Bc=5+\"
\n" ); document.write( "TWO \"+9a%2B3b%2Bc=8\"
\n" ); document.write( "THREE \"+c=2+\"\r
\n" ); document.write( "\n" ); document.write( "then you start with ONE and THREE
\n" ); document.write( "\"+a%5E2-b%2Bc=5+\"
\n" ); document.write( "\"+c=2+\" < multiply each side by -1
\n" ); document.write( "and add to get a-b=3\r
\n" ); document.write( "\n" ); document.write( "Im not sure if thats the way to go where you then use equation 3 to eliminate c from equation 2 or if there's another process to get solutions of a, b and c? I'm thankful for any advice on this problem!
\n" ); document.write( "
Great job in getting up to that point.
\n" ); document.write( "a - b + c = 5 ----- eq (i)
\n" ); document.write( "9a + 3b + c = 8 ----- eq (ii)
\n" ); document.write( "c = 2 ------ eq (iii)
\n" ); document.write( "Now, just substitute 2 for c in eq (i) to get: a – b = 3 ------- eq (iv)
\n" ); document.write( "Then, substitute 2 for c in eq (ii) to get: 9a + 3b = 6, which reduces to 3a + b = 2 ------- eq (v)\r
\n" ); document.write( "\n" ); document.write( "Now, ADD eqs (v) & (iv) to ELIMINATE b
\n" ); document.write( "From there, you should be able to find the values of a and b, you already have the value of c, so you have everything to form the equation. \n" ); document.write( "
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