question_answer

Construct \[\overline{AB}\]of length\[8.9\text{ }cm\]. From this, cut off \[\overline{AC}\] of length\[7.4\text{ }cm\]. Measure \[\overline{BC}\]

Answer:

Given, \[\overline{AB}=8.9\text{ }cm\] and \[\overline{AC}=7.4\text{ }cm\]. Now, to construct a line segment of length 8.9 cm, we use the following steps:

Step I: Draw a line I. Mark a point A on this line.

Step II: Place the pointer of compasses at the zero mark of the ruler. Open it to place the pencil point up to the 8.9 cm mark

Step III: Without changing the opening to the compasses. Place the pointer on A and swing an arc to cut I at B.

Step IV: \[\overline{AB}\] is a line segment of length 8.9 cm.

Now, to cut off \[\overline{AC}\] of length 7.4 cm from \[\overline{AB}\],  we use the following steps:

Step V: Now, place the pointer of compasses at the zero mark of the ruler. Open it to the place the pencil point up to 7.4 cm mark.                 ½

Step VI: Without changing the opening of the compasses, place the pointer on A and swing an arc to cut l at C.

Step VII: Now, \[\overline{AC}\] is a line segment of length 4.7 cm. On measuring, we get \[\overline{BC}\] = 1.5 cm.