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Matching method-formula method-cross multiplication two math problems?
x? -7X-60=0

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