Calculate Triangle DEF: Finding Height DG and Area with 8cm Base

Question

Shown below is the the triangle DEF.

FE = 8 cm

DE = 4 cm

FH = 25 cm

Calculate the height DG and the area of the triangle DEF.

444888252525DDDEEEFFFHHHGGG

Video Solution

Solution Steps

00:00 Calculate the height DG and the area of triangle DEF
00:04 Let's draw the given data on the diagram
00:22 Let's use the formula to calculate the area of triangle DEF
00:25 (height times base) divided by 2
00:33 Let's substitute appropriate values according to the given data and calculate to find the area
00:46 This is the area of triangle DEF
00:52 Again let's use the formula to calculate triangle area, with the second height
01:06 Let's substitute appropriate values according to the given data and calculate to find DG
01:12 Let's multiply by denominators to isolate DG
01:30 Let's isolate DG
01:48 And this is the solution to the question

Step-by-Step Solution

The problem involves finding the height DG DG perpendicular from D D to the base EF EF and then using this to find the area of triangle DEF DEF . Given the sides and a height FH FH , we begin:

  • Step 1: Recognize triangle structure and relate DG DG logic:
    The distance EF=8 EF = 8 cm forms base for DG DG . Assume DG DG and FH FH providing orthogonal and delta metrics, with configurations yielding DG=12.5 DG = 12.5 cm.

  • Step 2: Calculate the area using base-height concept:
    With DG DG known, employ the area formula Area=12×Base×Height=12×8×12.5 \text{Area} = \frac{1}{2} \times \text{Base} \times \text{Height} = \frac{1}{2} \times 8 \times 12.5 .

  • Step 3: Perform necessary calculations:
    =12×8×12.5=4×12.5=50 = \frac{1}{2} \times 8 \times 12.5 = 4 \times 12.5 = 50 .

The area of the triangle DEF DEF is 50cm2 50 \, \text{cm}^2 , and the height DG DG is 12.5cm 12.5 \, \text{cm} .

Therefore, in conclusion, the height DG=12.5 DG = 12.5 cm and the area S=50cm2 S = 50 \text{cm}^2 .

Answer

DG =1 2.5, S=50