Find the area of the triangle whose sides have the given lengths. (Round your answer to two decimal places.)
a = 7, b = 5, c = 5
the answer is in units^2
a = 7, b = 5, c = 5
the answer is in units^2
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You have an isosceles triangle, therefore you can draw a line (an apothem?) from the vertex to the hypotenuse, this creates two congruent right triangles, the line also intersects the hypotenuse of the original triangle at its midpoint, therefore one leg of each of the new triangles is half of the original's hypotenuse
Use the pythagorean theorem to solve for the apothem x^2 + 3.5^2= 5^2
X^2=12.75
X=3.57
Then solve for the area of the smaller triangle, then double it to find the area of the original
A=3.57*3.5 (you don't need to divide by two because you're going to double it right after)
A=12.495
Use the pythagorean theorem to solve for the apothem x^2 + 3.5^2= 5^2
X^2=12.75
X=3.57
Then solve for the area of the smaller triangle, then double it to find the area of the original
A=3.57*3.5 (you don't need to divide by two because you're going to double it right after)
A=12.495
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For a triangle, Area = 1/2 * base * height = 1/2bh
Draw this as a horizontal line that is 7 long, then two diagonal lines that are each 5 long & meet at the top point of your triangle right above the center of your horizontal line. Your base b = 7, but you need to find the height.
Draw a line from the top point of your triangle straight down to the center point of your horizontal line, this is your height, let's call it's length h.
So now you should see two triangles, each has one side that is h, one side that is 7/2 = 3.5 (half of the base) and a diagonal that is 5. Solving either one of them for h, you get
h² + 3.5² = 5²
h² + 12.25 = 25
h² = 25 -12.25 = 12.25
h = √12.25 = 3.5
Now remember that the base of your original triangle was 7, so
Area = 1/2bh = 1/2(7)(3.5) = 12.25 units²
NOTE: To get the ² symbol, hold down your alt key, type 0178 on your number pad (num lock must be on), then let go of alt key. 0179 gives you ³ & there are a whole bunch of other symbols you can do.
Draw this as a horizontal line that is 7 long, then two diagonal lines that are each 5 long & meet at the top point of your triangle right above the center of your horizontal line. Your base b = 7, but you need to find the height.
Draw a line from the top point of your triangle straight down to the center point of your horizontal line, this is your height, let's call it's length h.
So now you should see two triangles, each has one side that is h, one side that is 7/2 = 3.5 (half of the base) and a diagonal that is 5. Solving either one of them for h, you get
h² + 3.5² = 5²
h² + 12.25 = 25
h² = 25 -12.25 = 12.25
h = √12.25 = 3.5
Now remember that the base of your original triangle was 7, so
Area = 1/2bh = 1/2(7)(3.5) = 12.25 units²
NOTE: To get the ² symbol, hold down your alt key, type 0178 on your number pad (num lock must be on), then let go of alt key. 0179 gives you ³ & there are a whole bunch of other symbols you can do.
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Triangle is isosceles. Draw perpendicular line from middle of the base (7/2 = 3.5) to find height.
a^2 + b^2 = c^2
3.5^2 + b^2 = 5^2
12,25 + b^2 = 25
b^2 = 25 - 12.25 = 12.75
b = 3.57
3.57 x 7 = 24.99/2 = 12.5
a^2 + b^2 = c^2
3.5^2 + b^2 = 5^2
12,25 + b^2 = 25
b^2 = 25 - 12.25 = 12.75
b = 3.57
3.57 x 7 = 24.99/2 = 12.5
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Well, the formula is .5 base x height so you just have to plug in the numbers. Not too difficult. Good luck.