The diagonal of a rectangular field is 60m more than its breadth.If its length is 30m more than its breadth.find its length and breadth
Answers
Answer:
Let length of shorter side = x m
length of bigger side = (x + 30) m
length of diagonal = (x + 60) m
we have to use Pythagoras theorem,
so, diagonal ² = bigger side² + shorter side²
=> (x + 60)² = (x + 30)² + x²
=> x² + 120x + 3600 = x² + 60x + 900 + x²
=> 60x + 2700x = x²
=> x² - 60x - 2700 = 0
=> x² - 90x + 30x - 2700 = 0
=> x(x - 90) + 30(x - 90) = 0
=> x = -30 and 90 but x ≠ -30
hence, length of shorter side = 90m
length of bigger side = 120m
Given:
The diagonal of a rectangular field is 60m more than its breadth.If its length is 30m more than its breadth.
To find:
Its length and breadth of rectangular field.
Explanation:
- Let the breadth of rectangular field be R
- Let the length of rectangular field be R+30
- Let the diagonal of rectangular field be R + 60
Using Pythagoras Theorem:
[Hypotenuse]² = [base]² + [perpendicular]²
→ [Diagonal]² = [breadth]² + [length]²
→ (R + 60)² = (R)² + (R+30)²
[(a+b)² = a² + b² +2ab]
→ R² + 60² +2× R× 60 = R² + R² +30² + 2× R× 30
→ R² + 3600 + 120R = R² + R² + 900 + 60R
→ R² -R² + 120R -60R +3600 -900 = R²
→ 0 + 60R + 2700 =R²
→ R² -60R - 2700 = 0
[Factorization]
→ R² -90R +30R -2700= 0
→ R(R -90)+30(R -90) = 0
→ (R-90)(R+30) = 0
→ R -90=0 or R +30= 0
→ R = 90 or R= -30
Here, two value get, we know that negative value is not acceptable.
∴ R = 90m.
Thus,
- The breadth of the rectangular field = 90m
- The length of the rectangular field is (90+ 30)m =120m.