Advertisements
Advertisements
प्रश्न
In a ΔABC, if AB = AC and ∠B = 70°, find ∠A.
Advertisements
उत्तर
Consider , ΔABC we have `∠B=70^@` and AB =AC
Since, AB A C ABC is an isosceles triangle
⇒ ∠B=∠C [Angles opposite to equal sides are equal]
⇒`∠B = ∠C = 70^@`
And also,
Sum of angles in a triangle `180^@`
⇒ `∠A+∠B+∠C=180^@`
⇒`∠A+70^@+70^@=180^@`
⇒`∠A+140^@=180^@`
⇒`∠A=180^@-140^@⇒∠A=40^@`
APPEARS IN
संबंधित प्रश्न
BD and CE are bisectors of ∠B and ∠C of an isosceles ΔABC with AB = AC. Prove that BD = CE.
In the given figure, X is a point in the interior of square ABCD. AXYZ is also a square. If DY = 3 cm and AZ = 2 cm, then BY =
Observe the information shown in pair of triangle given below. State the test by which the two triangles are congruent. Write the remaining congruent parts of the triangles.
From the information shown in the figure,
In ΔABC and ΔPQR
∠ABC ≅ ∠PQR
seg BC ≅ seg QR
∠ACB ≅ ∠PRQ
∴ ΔABC ≅ ΔPQR ...`square` test
∴ ∠BAC ≅ `square` ...corresponding angles of congruent triangles.
`{:("seg AB" ≅ square),("and" square ≅ "seg PR"):}}` ...corresponding sides of congruent triangles
If the following pair of the triangle is congruent? state the condition of congruency :
In ΔABC and ΔDEF, ∠B = ∠E = 90o; AC = DF and BC = EF.
State, whether the pairs of triangles given in the following figures are congruent or not:
In the figure, BC = CE and ∠1 = ∠2. Prove that ΔGCB ≅ ΔDCE.
In the figure, AB = EF, BC = DE, AB and FE are perpendiculars on BE. Prove that ΔABD ≅ ΔFEC
ΔABC is isosceles with AB = AC. BD and CE are two medians of the triangle. Prove that BD = CE.
In ΔABC, AD is a median. The perpendiculars from B and C meet the line AD produced at X and Y. Prove that BX = CY.
If ∆PQR is congruent to ∆STU (see figure), then what is the length of TU?
