Question 1085654
Let {{{ a }}} = the number of rows of trees
Let {{{ b }}} = the number of trees in a row
{{{ a*b }}} = the total number of trees
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(1) {{{ a = b + 4 }}}
(2) {{{ ( b + 64 )*4 = a*b }}}
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(2) {{{ 4b + 256 = a*b }}}
(2) {{{ 4b + 256 = ( b + 4 )*b }}}
(2) {{{ 4b + 256 = b^2 + 4b }}}
(2) {{{ b^2 = 256 }}}
(2) {{{ b = 16 }}}
and
(1) {{{ a = b + 4 }}}
(1) {{{ a = 16 + 4 }}}
(1) {{{ a = 20 }}}
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{{{ a*b }}} = the total number of trees
{{{ a*b = 20*16 }}}
{{{ a*b = 320 }}}
There are 320 trees in the orchard
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check:
(2) {{{ ( b + 64 )*4 = a*b }}}
(2) {{{ ( 16 + 64 )*4 = 20*16 }}}
(2) {{{ 80*4 = 320 }}}
(2) {{{ 320 = 320 }}}
OK