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The area of a triangle is half the product of its base and its height.
Base: 11m
Height: 8m
We are told that the height of a triangle is 3m less than its base. Therefore, if we let b be the base, the height can be expressed as h=b-3. We are also told that the area is 44 square meters. Let's draw a diagram to illustrate the situation.
The area of a triangle is half the product of its base and its height.
A=1/2bh
A= 44, h= b-3
LHS * 2=RHS* 2
Distribute b
LHS-88=RHS-88
Rearrange equation
Note it's a quadratic equation. To solve this equation we will use the Quadratic Formula. ax^2+ bx+ c=0 ⇕ x=- b± sqrt(b^2-4 a c)/2 a The variable in our equation is b. Let's replace it with x not to mistake it with the b in the Quadratic Formula. b^2-3b-88=0 ⇕ x^2-3x-88=0 Next, we need to identify the values of a, b, and c. x^2-3x-88=0 ⇕ 1x^2+( - 3)x+( - 88)=0 We see that a= 1, b= - 3, and c= - 88. Let's substitute these values into the Quadratic Formula.
Substitute values
Now, we can go back to the previous notation and replace x with b. The solutions of our equation are b= 3 ± 192. Let's separate them into the positive and negative cases.
| b=3 ± 19/2 | |
|---|---|
| b_1=3+19/2 | b_2=3-19/2 |
| b_1=22/2 | b_2=- 16/2 |
| b_1=11 | b_2=- 8 |
Since b is the base of a triangle it must be positive. Therefore, the base of the triangle is 11m. The height is 3m less than its base, so we can subtract 3 from 11 to obtain the height. Height: 11-3=8 m