Question

If $△$ABC is drawn with length of side AB being 9 cm, $\angle$A being 45${}^{\circ }$ and $\angle$B being 65${}^{\circ }$, then the length of side AC is

• A. 6.9 cm
• B. 7.2 cm
• C. 7.9 cm
• D. 8.9 cm

Answer 1

The correct option is D

8.9 cm

Steps of construction of $△$ABC:

Step 1:
Draw the base line AB of the length 9 cm.

Step 2:
Measure the angle A with your protractor. Make a mark at 45 degrees and draw a line from A passing through the mark.

Step 3:
Measure the angle B with your protractor. Make a mark at 65 degrees and draw a line from B passing through the mark.

Step 4:
Name the point of intersection of these two lines as C and the $△$ABC is complete, as shown below.

Now, from the above construction, we see that the length of the side AC is 8.9 cm