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simultaneous equations watch

1. I'm having a bit of trouble with some simultaneous equations and any help would be appreciated.

1. s^2 + 2t^2 = 6
3s - t = 5

t = 3s - 5
s^2 + 2(3s - 5)^2 = 6
s^2 + 2(9s^2 - 30s + 25) = 6
s^2 + 18s^2 - 60s + 50 = 6
19s^2 - 60s = -44

Have i done something wrong here or am i getting it wrong?
Cheers in advance for any help.
2. You haven't made a mistake so far. The next step is to solve the quadratic equation:

3. If you're stuck on solving the quadratic equation, use the quadratic formula (it's probably easier than trying to factorise it).
4. ok i had to use the formula, and got x = 2 and x = 1 3/19. Hopefully that is right but out of curiosity how do you factorise with a number like 19 as 'a'?
cheers for the help
5. (Original post by delllboy)
ok i had to use the formula, and got x = 2 and x = 1 3/19. Hopefully that is right but out of curiosity how do you factorise with a number like 19 as 'a'?
cheers for the help
19 is a prime number, so the only way to factorise it would be 1 x 19:

Also, shouldn't it be s = 2 and s = 1 3/19 instead of x?
6. (Original post by starofale)
19 is a prime number, so the only way to factorise it would be 1 x 19:

Also, shouldn't it be s = 2 and s = 1 3/19 instead of x?
Yes it should; I've just got into a habit of saying x. There is no a or b though so i dont know how you got that.
7. (Original post by delllboy)
Yes it should; I've just got into a habit of saying x. There is no a or b though so i dont know how you got that.
Just replace a and b with numbers, I couldn't be bothered to work out what they should actually be.

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