Photo AI

Here is a right-angled triangle - OCR - GCSE Maths - Question 20 - 2018 - Paper 1

Question icon

Question 20

Here-is-a-right-angled-triangle-OCR-GCSE Maths-Question 20-2018-Paper 1.png

Here is a right-angled triangle. Not to scale Work out the value of x. The triangle has one side measuring 30 cm and another side measuring 8.4 cm. The side x cm ... show full transcript

Worked Solution & Example Answer:Here is a right-angled triangle - OCR - GCSE Maths - Question 20 - 2018 - Paper 1

Step 1

Use Pythagoras' Theorem

96%

114 rated

Answer

To find the length of side x in a right-angled triangle, we apply Pythagoras' theorem, which states that the square of the hypotenuse (longest side) is equal to the sum of the squares of the other two sides. Here, we can denote the sides as follows:

Let:

  • a = 8.4 cm (one side)
  • b = x cm (the other side)
  • c = 30 cm (the hypotenuse)

Thus, the equation is:

c2=a2+b2c^2 = a^2 + b^2

Substituting our values gives:

302=8.42+x230^2 = 8.4^2 + x^2

Step 2

Calculate and Solve for x

99%

104 rated

Answer

Now, we compute the squares:

302=90030^2 = 900 8.42=70.568.4^2 = 70.56

Substituting these into the equation:

900=70.56+x2900 = 70.56 + x^2

To isolate x2x^2, we subtract 70.56 from both sides:

x2=90070.56x^2 = 900 - 70.56 x2=829.44x^2 = 829.44

Next, we take the square root of both sides to solve for x:

x=ext(829.44)x = ext{√}(829.44)

Calculating this yields:

x28.8x ≈ 28.8

Step 3

Final Answer

96%

101 rated

Answer

Thus, the value of x is approximately 28.8 cm.

Join the GCSE students using SimpleStudy...

97% of Students

Report Improved Results

98% of Students

Recommend to friends

100,000+

Students Supported

1 Million+

Questions answered

;