Question 176153
Let C be the cost of carnations and D be the cost of daisies. 
1.{{{10C+5D=12.50}}}
2.{{{5C+8D=11.75}}}
Let's double eq. 2 and subtract 2 from 1 and solve for D.
{{{10C+5D-2(5C+8D)=12.5-2(11.75)}}}
{{{10C+5D-10C-16D)=12.5-23.50}}}
{{{-11D=-11}}}
{{{D=1}}}
From 1,
1.{{{10C+5D=12.50}}}
{{{10C+5=12.50}}}
{{{10C=7.50}}}
{{{C=0.75}}}
Carnations cost $0.75 while daisies cost $1.00.
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To do matrix multiplication, the inner dimensions (3) must match.
The product dimensions are the outer dimensions of the original matrices.
{{{(2x (highlight(3)))((highlight(3))x4)}}}

{{{(2x4)}}}
The product would be a 2x4 matrix.