Question

the area of a triangle is 90 cm 2. find the length of the base if it is 3 cm more than the height

Answer 1

let base be x cm
then height =x-3 cm
area=90=1/2×base×height
90×2=x × (x-3)
${x}^{2} - 3x - 180 \\ therefore \: root \: of \: eqution \: will \: be \\ x = 15 \: and \: x = - 12 \\ but \: side \: cant \: be \: negative \: therefore \: x = 15 \\ x = base = 15cm$