Question

$(3 \sqrt{7 } + 3 \sqrt{2} ) + (4 \sqrt{7} - 3 \sqrt{2} )$

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Answer 1

Like a door hinge, a hinge joint allows backward and forward movement. The pivot joint only allows rotating movement. An example of a pivot joint is the joint between the radius and ulna that allows you to turn the palm of your hand up and down.