Question 1054459
Let the angles be:
{{{ a }}} and {{{ b }}}
(1) {{{ a = 3b + 6 }}} degrees
(2) {{{ a + b = 90 }}} degrees
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(2) {{{ a = 90 - b }}}
Plug (2) into (1)
(1) {{{ 90 - b = 3b + 6 }}}
(1) {{{ 4b = 90 - 6 }}}
(1) {{{ 4b = 84 }}}
(1) {{{ b = 21 }}} degrees
and
(2) {{{ a = 90 - b }}}
(2) {{{ a = 90 - 21 }}}
(2) {{{ a = 69 }}} degrees