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Algebra e.g. 2x + 14 = 18. what is x?

2x + 14 = 18Whatever you do on one side, e.g. LHS, you do the same on the RHS.-14 from both sides 2x + 14 (-14) = 18 (-14)2x = 4To get x by itself you need to divide it by 2. so you divide LHS and RHS by 2.x...
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Answered by Sonam T. Maths tutor
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Ultrasound is used to scan unborn babies but X-rays are not used to scan unborn babies.

Ultrasound is not ionising as it is a longitudinal wave whilst X-rays are ionising as they are transverse waves and have very high frequency hence can 'knock' electrons out of their orbit. Doing this can cau...
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Answered by Saram A. Physics tutor
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Prove that the sum of two consecutive integers is always odd

And integer is a whole numberLet the integer = 2X meaning it is even and the next number is (2X+1) making it oddTherefore the sum of the two consecutive integers is2X + 2X + 1=4X+1As this cannot be factorise...
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Answered by Scott S. Maths tutor
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Factorise 3x^3y^2-6x^2y+9xy

look for a common factor. See that 3 divides 3, -6 and 9. Then see that x and y divide the equation also. so write 3xy(x 2 y-2x+3) and this is your answer.
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Answered by Amber S. Maths tutor
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The point P has coordinates (3, 4) The point Q has coordinates (a, b) A line perpendicular to PQ is given by the equation 3x + 2y = 7 Find an expression for b in terms of a.

Draw a diagramRearrange the given equation into the form y = mx + cy = -3/2x+7/2Gradients of perpendicular lines - m1*m2=-1, so gradient of PQ = 2/3PQ : y=mx+c -> 4=(2/3)*3+cc=2, therefore PQ: y=2/3x+2 b=...
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Answered by Jack W. Maths tutor
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