7. Given the area of the non-shaded region is 315 square feet, find the base and height of the large triangle X + 6 2x +2 3x + 5 + Base= feet Height = feet

7 Given the area of the nonshaded region is 315 square feet find the base and height of the large triangle X 6 2x 2 3x 5 Base feet Height feet class=

Respuesta :

Answer:

Explanation:

The height of the triangle is

[tex]2x+2+x+6=3x+8[/tex]

the base length is

[tex]2(3x+5+3)=6x+16[/tex]

Therefore, the area of the larger triangle is

[tex]Area=(6x+16)(3x+8)[/tex]

Similarly, the area of the shaded triangle is

[tex](x+6)(3x+5)[/tex]

Therefore, the area of the unshaded region is

[tex](6x+16)(3x+8)-(x+6)(3x+5)[/tex]

which simplifies to give

[tex]15x^2+73x+98[/tex]

and we know that the area of the unshaded region is 315 and so

[tex]15x^2+73x+98=315[/tex]

which simplifies to give

[tex]15x^2+73x-217=0[/tex]

and the solution to the equation is

[tex]x=2.082[/tex]

With the value of x in hand, we now find the base and height lengths.

[tex]\begin{gathered} height=3x+8=3(2.082)+8 \\ \boxed{height=14.246} \end{gathered}[/tex]

and

[tex]\begin{gathered} base=6x+16=2(2.082)+16 \\ \boxed{base=20.164} \end{gathered}[/tex]

Hence,

height = 14. 246

base = 20.164