Advertisements
Advertisements
Question
In ΔABC, D and E are the mid-point on AB and AC such that DE || BC.
If AD : BD = 4 : 5 and EC = 2.5cm, find AE.
Solution
In ΔADE and ΔABC
∠D = ∠B and ∠C = ∠E ...(DE || BC)
⇒ ΔADE ∼ ΔABC
∴ `"AD"/"DB" = "AE"/"EC"`
⇒ `(4)/(5) = "AE"/(2.5)`
⇒ AE = `(4 xx 2.5)/(5)`
⇒ AE = 2cm.
APPEARS IN
RELATED QUESTIONS
In a triangle ABC, line l || Side BC and line l intersects side AB and AC in points P and Q, respectively. Prove that: `"AP"/"BP"="AQ"/"QC"`
In the following figure, if LM || CB and LN || CD, prove that `("AM")/("AB")=("AN")/("AD")`
The perimeters of two similar triangles are 25 cm and 15 cm respectively. If one side of first triangle is 9 cm, what is the corresponding side of the other triangle?
State, true or false:
All equiangular triangles are similar.
The corresponding altitudes of two similar triangles are 6cm and 9cm respectively. Find the ratio of their areas.
On a map drawn to a scale of 1 : 25000, a rectangular plot of land, ABCD is measured as AB= 12 cm and BC = 16cm. calculate the diagonal distance of the plot in km and the plot area in km2 .
A triangle ABC is enlarged, about the point O as centre of enlargement, and the scale factor is 3. Find : OC', if OC = 21 cm.
Also, state the value of :
- `(OB^')/(OB)`
- `(C^'A^')/(CA)`
The given figure shows a parallelogram ABCD. E is a point in AD and CE produced meets BA produced at point F. If AE = 4 cm, AF = 8 cm and AB = 12 cm, find the perimeter of the parallelogram ABCD.
Choose the correct alternative:
If ΔABC ~ ΔPQR and 4A (ΔABC) = 25 A(ΔPQR), then AB : PQ = ?
ΔABC and ΔBDE are two equilateral triangles such that D is the mid point of BC. Ratio of the areas of triangle ΔABC and ΔBDE is ______.