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Make x the subject of the following formula: 5(3x -2y) = 14 - 2ax

(1) 5(3x - 2y) = 14 -2ax 15x - 10y = 14 - 2ax (2) 15x +2ax -10y = 14 15x + 2ax = 10y + 14
(3) x(15 + 2a) = 10y + 14 x = (10y + 14) / (15 + 2a)
To asking us to make x the subject of a fo...

Answered by Thomas W. • Maths tutor

4255 Views

Solve these simultaneous equations: 3xy = 1, and y = 12x + 3

From first equation: 3xy = 1 => x = 1/(3y)Substitute expression for x into second equation: y = 12x + 3 => y = 12(1/3y) + 3 = 4/y +3Multiply through by y: y² = 4 + 3y => y²

Answered by Hallam M. • Further Mathematics tutor

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A is the point (2,-5), B is the point (-1,4). (a) What is the gradient of the line passing through points A and B? (b) Does the point (-100,301) lie on the line passing through points A and B?

(a) let A be (x1,y1) and B be (x2,y2), Gradient = m = (y2-y1)/(x2-x1) m = (4- -5)/(-1-2) = 9/(-3) = -3 Gradient = -3
(b) equation of a straight line line: y = mx + c => y1 = ...

Answered by Hallam M. • Maths tutor

3705 Views

What is the difference between the function of platelets, white blood cells and red blood cells?

They are all components of blood. Platelets are small fragments of cells and help blood to form clots. This stops the body from bleeding when a blood vessel gets damaged. White blood cells destroy microor...

Answered by Tutor313352 D. • Biology tutor

3784 Views

Factorise: x^2+2x-3

think of it in the form of Ax^2 +Bx +C. Most of the GCSE examples will have A as zero so we will ignore the A. To factorise this you need to find what two numbers multiply to make C and adds to make B. In...

Answered by Katherine A. • Maths tutor

3927 Views