Q. The length of a rectangle's diagonal is 229, and the length of the longer side is 10 . What is the area of the rectangle?A) 116B) 2029C) 1029D) 40
Identify Rectangle Dimensions: To find the area of the rectangle, we need to know both the length and the width. We already know the length is 10. We can use the Pythagorean theorem to find the width, since the diagonal (d), length (l), and width (w) of a rectangle form a right triangle: d2=l2+w2.
Calculate Diagonal Squared: We are given that the diagonal d is 229. Let's square this to find d2: (229)2=4×29=116.
Calculate Length Squared: We know the length l is 10, so let's square this to find l2: 102=100.
Substitute into Pythagorean Theorem: Now we can substitute d2 and l2 into the Pythagorean theorem to find w2: 116=100+w2.
Solve for Width: Subtract 100 from both sides to solve for w2: 116−100=w2, so w2=16.
Find Width: Take the square root of both sides to find w: w2=16, so w=4.
Calculate Area: Now that we have both the length (10) and the width (4), we can find the area of the rectangle by multiplying the length by the width: Area=length×width=10×4.
Final Area Calculation: Calculate the area: 10×4=40.