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Fully factorise and simplify (x^2 +7x + 10) / (x^2 - 25)

Simplify the numerator (top) by finding the pair of numbers which multiply together to give the C term of the quadratic, and add to give the B term. This gives 2 and 5 so the equation becomes (x+2)(x+5) / (x...
NP
Answered by Nikolai P. • Maths tutor
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What type of studies can be used to assess the extent to which genes can cause psychopathology?

Twin studies are exceptionally important when studying the effect of genes on behaviour and psychopathology. Twins can be MZ (monozygotic) twins who share 100% of their DNA so they have identical genotypes, ...
GW
Answered by Gemma W. • Psychology tutor
2378 Views

Two beakers contain water at room temperature. One contains 200ml, the other 400ml. If both beakers are heated above identical Bunsen burners, which of the two will take longer to boil?

The equation dQ = m c dT tells us how the temperature of an object changes when heat energy dQ is added. In this case the specific heat capacity c is the same for the contents of both beakers since we are he...
KJ
Answered by Keita J. • Physics tutor
7414 Views

A house is bought for £150,000 at the start of 2005. For 3 years it loses 10% of its original value per year. After this time it loses 10% per year. What was its value at the end of 2011/start of 2012?

Original value = 150,000 10% original value =15,000 After 3 years year is 2008, house value = 150,000 - 3*(15,000) = 105,000Until start of 2012 from start of 2008, so 4 years of compound intrest. New value o...
HF
Answered by Henry F. • Maths tutor
3603 Views

If a student wishes to have a ratio of 2:7 red pens to yellow pens in their pencil case: a) if they have 50 pens total what is the maximum amount they can carry with them b) if they have 18 red and 31 yellow what is the maximum amount they can carry

a) 50 pens total. 2 + 7 = 9. Number of pens is done in 9s. 50/9 = 5r5, so multiple of 5. Then 2 5 + 7 5 pens. 10 red and 35 yellow, 45 pens b) 18 red / 2 = [9]r0 31 yellow / 7 = [4]r3 So could have 9 sets of...
HF
Answered by Henry F. • Maths tutor
3500 Views