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I hope you can learn mathematics. The mathematic is difficult and fearfull. Matematika. PYTHAGOREAN THEOREM. CLASS : VIII SEMESTER : 1 B Y SULISTYANA , S.Pd. SMP 1 WONOSARI GK. LANJUT. REMEMBER.
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I hope you can learn mathematics The mathematic is difficult and fearfull Matematika
PYTHAGOREAN THEOREM CLASS : VIII SEMESTER : 1 B Y SULISTYANA, S.Pd. SMP 1 WONOSARI GK LANJUT
REMEMBER Triangles can be classified according to the length of their sides. They can be classified as either equilateral, isosceles or scalene.
Triangles can be classified bytheir angles as well. A triangle with one right angle is said to be a right triangle. Right triangle
In any triangle, the longest side is opposite the largest angle; soin a right triangle, the longest side is opposite the rightangle. This side has a special name. It is called the hypotenuse.
Pythagorean Theorem In any right angled triangle, the square of the hypotenuse is equal to the sum of the squares of the other two sides. The rule is written asc2 = a2 + b2where a and b are the two shorter sides and c is the hypotenuse. The hypotenuse is the longest side of a right-angled triangleand is always the side that is opposite the right angle.
Finding the hypotenuse We are able to find the length of the hypotenuse when we are given the length of thetwo shorter sides by substituting into the formulac2 = a2 + b2
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Finding a shorter side Sometimes a question will give you the length of the hypotenuse and ask you to findone of the shorter sides. In such examples, we need to rearrangePythagoras’ formula. Given that c2 = a2 + b2, we can rewrite this as:a2 = c2 - b2or b2 = c2 + a2.
2. The diagonal of the rectangular sign at right is34 cm. If the height of this sign is 25 cm, find the width. 3 The diagonal of a rectangle is 120 cm. One sidehas a length of 70 cm. Find: a the length of the other side b the perimeter of the rectangle c the area of the rectangle. 4 An equilateral triangle has sides of length 20 cm. Findthe height of the triangle. 5 The road sign shown at left is in the form of anequilateral triangle. Find the height of the sign and, hence, find its area. 6 A ladder that is 7 meter long leans up against a vertical wall. The top of the ladder reaches 6.5 m up the wall. How far from the wall is the foot of the ladder? 7 A tent pole that is 1.5 m high is to be supportedby ropes attached to the top. Each rope is 2 mlong. How far from the base of the pole can each rope be pegged?