Question

A, B & C form a triangle where Z BAC = 90°.

AB = 4.2 mm and CA = 1.5 mm.
Find the length of BC, giving your answer rounded to 1
DP.
mm
BC =

Answer 1

Explanation:

Nothing further can be done with this topic. Please check the expression entered or try another topic.

A, B, C, ZBAC=90°

AB=4.2mm

CA=1.5mm,

DP

mm

BC

hope this helps

Answer 2

BC = 4.5 (1 dp)

Explanation:

Pythagoras’ Theorem

`a^2+b^2=c^2`

(where a and b are the legs, and c is the hypotenuse, of a right triangle)

Given:

• a = AC = 1.5
• b = AB = 4.2
• c = BC

Substituting these into the formula and solving for BC:

`\implies 1.5^2+4.2^2=BC^2`

`\implies 2.25+17.64=BC^2`

`\implies BC^2=19.89`

`\implies BC=\pm√(19.89)`

As distance is positive,

⇒ BC = 4.5 (1 dp)