Decimal problem using solve

[Albert Chan]

(08-26-2018 07:22 PM)Albert Chan Wrote:  70*y = x*177.35+(1-x)*1.133
(x*2571.11+(1-x)*696.21) = (2779.65*(23000+z) + 23000*(104.91-2779.65)) / (23000+z) = 2779.65 - 61519020*y

Above simplified to linear equations ...

I noticed another trick to solve above, with regression mode of my Casio
Above problem look exactly like interpolation within interval

70*y = i1(x)
i2(x) = 2779.65 - 61519020*y

Let Y = 61519020 i1(x) + 70 i2(x). To satisfy above, Y = 70 * 2779.65

At x=0, Y = 61519020 * 1.133 + 70 * 696.21
At x=1, Y = 61519020 * 177.35 + 70 * 2571.11

Enter these 2 points for linear regression, interpolate for Y = 70 * 2779.65, I get x = -6.41604187e-3