84а+25а+7=443
109a+7=443
109a=443-7
109a=436
a=436/109
а=4
486:(5х+2)=18
18(5x+2)=486
90x+36=486
90x=486-36
90x=450
х=5
84а+25а+7=443
109a+7=443
109a=443-7
109a=436
a=436/109
а=4
486:(5х+2)=18
18(5x+2)=486
90x+36=486
90x=486-36
90x=450
х=5