Question

add 9x/5,3/5y, (3/2-1)x​

Answer 1

30

B

C С

Fig. 3.29

Construction : Take a point D on the extended

seg AB such that AB = BD. Draw seg DC.

Proof : /\ ABC and /\ DBC

seg AB seg DB

___________

angle ABC segment Angle DBC________

seg BC seg BC_______

.. A ABC = A DBC________

Fig. 3.30

... angle BAC angleBDC (c.a.c.t.)

In A ABC, ZBAC = 60° . ZBDC = 60°

ZDAC = ZADC = ZACD = 60°... sum of angles of A ADC is 180°Kk

.: AADC is an equilateral triangle.

.. AC = AD = DC ........ corollary of converse of isosceles triangle theorem

1

But AB = AD........ construction

2

1

..AB AC ........ * AD= AC

2

1 / 2Proof : /\ ABC and /\ DBC

seg AB seg DB

___________

angle ABC segment Angle DBC________

seg BC seg BC_______

.. A ABC = A DBC________

Fig. 3.30

... angle

1

..AB AC ........ * AD= AC

2

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