Worked Solution & Example Answer:15 (a) Solve - OCR - GCSE Maths - Question 15 - 2020 - Paper 1
Step 1
Solve.
\( \frac{x + 5}{2} = 15 \)
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Answer
To solve the equation, first multiply both sides by 2:
x+5=30
Next, subtract 5 from both sides:
x=30−5
Finally, this simplifies to:
x=25
Step 2
Factorise.
\( 5a^2 - 10a \)
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Answer
To factorise the expression, first identify the common factor, which is 5a:
5a(a−2)
Thus, the factorised form is:
5a(a−2)
Step 3
Solve by factorising.
\( x^2 + 15x + 56 = 0 \)
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Answer
To solve this quadratic equation by factorising, we look for two numbers that multiply to 56 and add to 15. The numbers 7 and 8 meet this requirement. Therefore, we can write:
