The answer is D. How do I get that?

lenpol72021-04-05T10:16:05Z

Being an Isoscles Triangle (two equal sides) , dropping a perpendicular to the base of '2' will bisect the base line, into 1 + 1 = 2 and intersect at right angles.  So we have two right angled triangles 'inside' the Isosceles triangle.
Next apply Pythagoras, to find the  perpendicular height . 
6^2 = 1^2 + h^2 
h^2 = 6^2 - 1^2 
h^2 = (6 - 1)(6 + 1) 
h^2 = 5(7)
h^2 = 35 
h = sqrt(35) 
Next remember the Area = 0.5 X base X perpendicular height
A = 0.5 X 2 X sqrt(35) 
A = sqrt(35)  
NB 0.5 X 2 = 1 
Answer 'D'. 

oubaas2021-04-04T08:03:48Z

h = √6^1-(2/2)^2 = √35
area = b*h/2 = 2√35 / 2 = √35

or by applying Heron's formula 
semi-perimeter sp = (6+6+2)/2 = 7 
area = √sp*(sp-a)*(sp-b)*(sp-c) = √7*(7-6)*(7-6)*(7-2) = √7*1*1*5 = √ 35 

llaffer2021-04-03T00:11:40Z

Or you can use Herron's Formula to get the area of the triangle given the length of the three sides:

A = √[s(s - a)(s - b)(s - c)] where s = (a + b + c) / 2

So we can find s, then find A:

s = (a + b + c) / 2
s = (6 + 6 + 2) / 2
s = 14 / 2
s = 7

A = √[s(s - a)(s - b)(s - c)]
A = √[7(7 - 6)(7 - 6)(7 - 2)]
A = √[7(1)(1)(5)]
A = √35 yd²

Daniel H2021-04-02T23:37:06Z

Cut in half. flip around. Now you have a rectangle.

width = 1
height = sqrt(6^2 - 1^2) = sqrt(35)

Area = width * height = 1 * sqrt(35)

Amy2021-04-02T23:30:50Z

Draw a line down the center, splitting the triangle into two smaller right triangles.
Each* right triangle has a base of length 1 and a hypotenuse of 6. You can thus apply the Pythagorean Theorem to find the height.
Finally, apply the formula for area of a triangle.

* For proof that the perpendicular line does bisect the base: 
Whatever the height is, both right triangles have the same height and hypotenuse; therefore by Pythagoras their bases are identical.

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