Answer:
[tex]70\sqrt{2}[/tex]
Step-by-step explanation:
Since angle A is 45, the height of the base BC is 10/[tex]\sqrt{2}[/tex] by 1-1-sqrt(2) triangles.
Then we can apply parallelogram area formula.
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Explanation:
One formula you can use is
A = b*c*sin(theta)
where angle theta is between sides b and c
Note how angle A is between sides AB = 10 and AD = BC = 14.
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Using that formula gives
A = b*c*sin(theta)
A = 10*14*sin(45)
A = 140*sin(45)
A = 140*sqrt(2)/2 ... use unit circle
A = (140/2)*sqrt(2)
A = 70*sqrt(2)
