document.write( "Question 987518: The height of a triangle is 4 m more than twice the length of the base. The area is 15m2. Find the height of the triangle. \n" ); document.write( "

Algebra.Com's Answer #608267 by algebrahouse.com(1659) $\"\"$ $\"About$

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base x height
\n" ); document.write( "------------- = area of a triangle
\n" ); document.write( "2\r
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\n" ); document.write( "\n" ); document.write( "b = base
\n" ); document.write( "2b + 4 = height {the height is 4 more than twice the base}\r
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\n" ); document.write( "\n" ); document.write( "b(2b + 4)
\n" ); document.write( "--------- = 15 {substituted base and height into area formula}
\n" ); document.write( "2\r
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\n" ); document.write( "\n" ); document.write( "b(2b + 4) = 30 {multiplied each side by 2}
\n" ); document.write( "2b² + 4b = 30 {used distributive property}
\n" ); document.write( "b² + 2b = 15 {divided entire equation by 2}
\n" ); document.write( "b² + 2b - 15 = 0 {subtracted 15 from each side}
\n" ); document.write( "(b + 5)(b - 3) = 0 {factored into two binomials}
\n" ); document.write( "b + 5 = 0 or b - 3 = 0 {set each factor equal to 0}
\n" ); document.write( "b = -5 or b = 3 {subtracted 5 and added 3 to the equations}\r
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\n" ); document.write( "\n" ); document.write( "base cannot be -5\r
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\n" ); document.write( "\n" ); document.write( "base = 3 m
\n" ); document.write( "height = 10 m {since 2b + 4 was the height}
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