If an equilateral triangle,a square and a circle are drawn on a piece of paprer, what is the maximum number of their intersection?
Trình bày cách giải thì đc chọn
A certain number of fifty-cent coins is to from an equilateral triangle. The same number of fifty-cent coins can also be used to from a square. The number of fiftty-cent coins on each side of the square is 6 fewer than the number of fifty-cent coins on each side of the equilateral traingle. How many fifty-cent coins are there altogether?
an equilateral triangle of side 12 has its conrner cut off to form a regular hexagon
a) what is the area of the corner cut off?
b) find the are of the
Given a square with the length of one side is 8 cm and a isosceles triangle with the length of its base is 12 cm. If the area of the square is equal to the area of the isosceles triangle then what is the length of the height of the isosceles triangle, in cm?
1. Two bisector BD and CE of the triangle ABC intersect at O. Suppose that BD.CE = 2BO.OC . Denote by H the point in BC such that .\(OH⊥BC\) . Prove that AB.AC = 2HB.HC
2. Given a trapezoid ABCD with the based edges BC=3cm , DA=6cm ( AD//BC ). Then the length of the line EF ( \(E\in AB,F\in CD\) and EF // AD ) through the intersection point M of AC and BD is ............... ?
3. Let ABC be an equilateral triangle and a point M inside the triangle such that \(MA^2=MB^2+MC^2\) . Draw an equilateral triangle ACD where \(D\ne B\) . Let the point N inside \(\Delta ACD\) such that AMN is an equilateral triangle. Determine \(\widehat{BMC}\) ?
4. Given an isosceles triangle ABC at A. Draw ray Cx being perpendicular to CA, BE perpendicular to Cx \(\left(E\in Cx\right)\) . Let M be the midpoint of BE, and D be the intersection point of AM and Cx. Prove that \(BD⊥BC\)
Let ABCD be a trapezoid with bases AB, CD and O be the intersection of AC and BD. If the areas of triangle OAB, triangle OCD are 16cm2, 40cm2respectively and M is the midpoint of BD, then the area of the triangle AMD is .........cm2.
Let ABCD be a trapezoid with bases AB, CD and O be the intersection of AC and BD. If the areas of triangle OAB, triangle OCD are 16cm2, 40cm2respectively and M is the midpoint of BD, then the area of the triangle AMD is .........cm2.
đựng đường cao 2 bên áp dụng 2 tam giác đồng dạng suy ra tỉ số diện tích
đáp án 22 cm2
A square and a triangle have equal perimeters. The lengths of three sides of the triangle are 6.2cm, 8.3cm and 9.5cm. The area of the square is...
Perimeters of a triangle is: 6.2+8.3+9.5=24cm
But a square and a triangle have equal perimeters
⇒Perimeters of a square is 24cm
So: the side of a square=\(\dfrac{24}{4}\)=6
Other way: the area of a square=a.a
⇔Ssquare=6*6=36 (cm2)
The sides of a triangle are a, b and c respectively. What is the perimeter of the triangle if a = 5cm, b = 4cm, and c = 3cm? Answer: The perimeter of the triangle is cm.