Question

求解2元2次方程组!求解此方程组：X^2+Y^2=7225 （140-X）^2+（Y-12.5）^2=9506.25

Answer 1

X^2+Y^2=7225

(140-X)^2+(Y-12.5)^2=9506.25

相减

280x-140^2+25y-12.5^2= - 2281.25

280x-25y = 17475

56x-5y = 3495

5y = 3495 - 56x

25x^2+(5y)^2 = 7225*25

25x^2+(3495 - 56x )^2 = 7225*25

3161x^2-391440x [phone]=0

Δ=1062320000

x1 = 391440+32593.25 / 2*3161 =67

x2 = 391440-32593.25 / 2*3161 = 56.76

y的4个值代这里面就行了5y = 3495 - 56x