4(x-3)² = 60 please help me solve. we cant use calculators?
回答 (4)
2010-03-04 2:46 pm
✔ 最佳答案
4(x-3)² = 60 4(x^2-6x+9)=60
4x^2-24x+36=60
4x^2-24x+36-60=0
4x^2-24x-24=0
x^2-6x-6=0
x^2-6x=6
now, use completing the square:
x^2-6x+9=15
(x-3)^2=15
x-3=±√(15)
x=3±√(15)
x=3+√(15), 3-√(15) answer//
2010-03-04 3:03 pm
4(x - 3)^2 = 60
(x - 3)^2 = 60/4
x - 3 = 屉15
x = 3 ± â15
(x - 3)^2 = 60/4
x - 3 = 屉15
x = 3 ± â15
2010-03-04 2:38 pm
you can try this:
4(x-3)^2 =60
4[(x-3)(x+3)]=60
4[x^2-3x+3x-9]=60
4x^2-36=60
4x^2=96
x^2=24
x=square root of 24.
4(x-3)^2 =60
4[(x-3)(x+3)]=60
4[x^2-3x+3x-9]=60
4x^2-36=60
4x^2=96
x^2=24
x=square root of 24.
2010-03-04 2:32 pm
4(x - 3)^2 = 60
(x - 3)^2 = 15
x - 3 = ± â15
x = 3 ± â15
My hand never touched a calculator!
(x - 3)^2 = 15
x - 3 = ± â15
x = 3 ± â15
My hand never touched a calculator!
參考: I have taught math for over 40 yr.
收錄日期: 2021-05-01 13:04:00
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