Question 942486
An integer is just a counting number, but it can
be + or -
Let the integers be {{{ a }}} and {{{ b }}}
given:
(1) {{{ a = 2b - 4 }}}
(2) {{{ a*b = 70 }}}
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Substitute (1) into (2)
(2) {{{ ( 2b - 4 )*b = 70 }}}
(2) {{{ 2b^2 - 4b = 70 }}}
(2) {{{ b^2 - 2b = 35 }}}
(2) {{{ b^2 - 2b - 35 = 0 }}}
(2) {{{ ( b + 5 )*( b - 7 ) = 0 }}} ( by looking at it )
{{{ b = 7 }}}
Now find {{{ a }}}
(2) {{{ a*b = 70 }}}
(2) {{{ a = 70/b }}}
(2) {{{ a = 70/7 }}}
(2) {{{ a = 10 }}}
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7 and 10 are solutions
check:
(1) {{{ a = 2b - 4 }}}
(1) {{{ 10 = 2*7 - 4 }}}
(1) {{{ 10 = 10 }}}
OK
Note that {{{ b = -5 }}} will also work. Just find 
{{{ a }}} the same way, and you have another solution
Hope this helps