Matching method: x? -7X+3.5? =72.25
(X-3.5)? =72.25
X-3.5=8.5 or X-3.5=-8.5.
X= 12 or X=-5.
Cross multiplication: x? -7X-60=0
(X- 12)(X+5)=0
X= 12 or X=-5.
Formula method: x? -7X-60=0
X=(7+√49+240)/2= 12 or X=(7-√49+240)/2=-5.
4X? -3X- 1=0
Matching method: 4X? -3X- 1=0
4(X? -3/4X+9/64)=25/ 16
(x-3/8)? =25/64
X-3/8=5/8 or X-3/8=-5/8.
X= 1 or X=- 1/4.
Cross multiplication: 4X? -3X- 1=0
(4X+ 1)(X- 1)=0
X= 1 or X=- 1/4.
Formula method: 4X? -3X- 1=0
X=(3+√9+ 16)/8= 1 or x = (3-√ 9+1 6)/8 =-14,1,and the matching method of two math problems.
x? -7X-60=0
4X? -3X- 1=0
Both should be written by distribution method and cross multiplication formula method.
3Q