90/139 is the only fraction not equivalent to 45/70.
To find if a fractions are equivalent, divide the numerator by the denominator for each fraction.
45/70=0.642857
27/42=0.642857
9/14=0.642857
63/98=0.642857
Notice how all of these get you the same number. However, when you divide 90 by 137, you get 0.64748, which is not the same as the others. Therefore, 90/137 is the fraction that is not equivalent to 45/70.
What is the solution set of x2 + y2 = 26 and x − y = 6? A. {(5, -1), (-5, 1)} B. {(1, 5), (5, 1)} C. {(-1, 5), (1, -5)} D. {(5,
Rus_ich [418]
He two equations given are
x^2 + y^2 = 26
And
x - y = 6
x = y +6
Putting the value of x from the second equation to the first equation, we get
x^2 + y^2 = 26
(y + 6) ^2 + y^2 = 26
y^2 + 12y + 36 + y^2 = 26
2y^2 + 12y + 36 - 26 = 0
2y^2 + 12y + 10 = 0
y^2 + 6y + 5 = 0
y^2 + y + 5y + 5 = 0
y(y + 1) + 5 ( y + 1) = 0
(y + 1)(y + 5) = 0
Then
y + 1 = 0
y = -1
so x - y = 6
x + 1 = 6
x = 5
Or
y + 5 = 0
y = - 5
Again x = 1
So the solutions would be (-1, 5), (1 , -5). The correct option is option "C".
Trinomial 2x² + 4x + 4.
It's of the form ax²+bx+c and it's discriminant is Δ=b² - 4.a.c
(in our case Δ = 4² - (4)(2)(4) → Δ = - 32
We know that: x' = -1 + i and x" = -1 - i
If Δ > 0 we have 2 rational solutions x' and x"
If Δ = 0 we have1 rational solution x' = x"
If Δ < 0 we have 2 complex solutions x' and x", that are conjugate
In our example we have Δ = - 16 then <0 so we have 2 complex solutions
That are x'= [-b+√Δ]/2.a and x" = [-b-√Δ]/2.a
x' =
first of all b. is 6 because you need to mow 6 lawns in order to get 160$ in one week
but im still trynna figure out a so gimme a sec
