That would be (y - 9)(y +9). When two binomials are multiplied, the distributive property is applied. However, if the equation is <span>y(3)(-3)y(3)(3), you just simply multiply them altogether. That would be -81y^2, which is not equivalent with y^2 - 81.</span>
This in what I got:
(-7i)(10i)
-70i
There is no given data table but based on the question, the reaction is
xy <=> x + y
If we let M as the initial concentration of xy and c as the in the concentration after the dissociation, then we can use the ICE method
xy <=> x + y
I M
C -c c c
-----------------------------
E M-c c c
Solve for c using
Kc = c(c) / (M - c)
And the concentration of the xy, x, and y can then be determined
Ef=19, as given in the question.
