Question

please some one help me in solving this question from grade 6 i will mark him or her briliant answer

Answer 1

Answer:

1)in first figure you have been given a right angle triangle

so one side is 9.6 cm and other side will be half of 15.4

then use Pythagoras theorem to find the x

2) in the second figure one side is 19 cm other side will be (8+6) = 14 cm

then use Pythagoras theorem to find the third side

then take 8 cm as base and with the help of the third side use Pythagoras theorem to find c

Answer 2

Answer:

x = 5.73 m.

c = 15.13 cm

Step-by-step explanation:

In the diagram on the top:

AB = AC, ∴ ΔABC is isosceles and ∠ABC = ∠ACB

Between ΔABD and ΔACD, both of these are right angled.  

Hypotenuse, AB = AC, ∠ABD = ∠ACD

∴ By SAA rule, ΔABD ≅ ΔACD

∴ BD = CD = $\frac{15.4}{2}$ m = 7.7 m

∴ $x^2 =$ $AB^2 - BD^2$ $= (9.6)^2 - (7.7)^2$

= (9.6 + 7.7)(9.6 - 7.7)  [using the identity $a^2 - b^2 = (a + b)(a - b)$]

= 17.3x1.9

=32.87

∴ x = 5.73 m.

In the diagram at the bottom:

ΔABC and ΔADC are right angled triangles.

By Pythagoras's rule, $AC^2 = AB^2 - BC^2$ $= (19^2 - 14^2) cm^2 = (19 - 14)(19 + 14) cm^2= (5).(33) cm^2 = 165 cm^2$

Again, $AD^2 = AC^2 + CD^2 =$ (165 + 64) $cm^2$ = 229 $cm^2$

∴ c = AD = 15.13 cm