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Could someone help me with these math problems? I can't figure them out. Solve the linear equation;
x+2y=15
y=-2x+0 9x-12y=-3
-12x+16y=4? Current in a circuit increases linearly from 0 to 5A over 5 second total charge flowing through cicuit over duration is seniors plz give ans? =B y I y is an integer and ≤−4 White light is directed at difraction grating at angle normal to gratting.starting at norml to grating 0dgre the odr of red,gren,blue wil be? Verify that M(u,v)=A +u(B-A) +v(C -A) ( A,B,C vectors) is a parametric representation of surface of the triangle A(1,0,0) B(0,-1,2) C(0,2,1)?