diff --git a/source/linear-algebra/source/02-EV/03.ptx b/source/linear-algebra/source/02-EV/03.ptx
index 2002e7d93..fbe67f994 100644
--- a/source/linear-algebra/source/02-EV/03.ptx
+++ b/source/linear-algebra/source/02-EV/03.ptx
@@ -343,7 +343,7 @@ we'll learn what this means more carefully in a later chapter.
A planar subset of \IR^3 compared with the plane \IR^2.
-
+
A planar subset of \IR^3.
@@ -362,6 +362,18 @@ p += plot(vector([3,-1]), color="yellow")
p
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@@ -1108,7 +1120,7 @@ that is, (kx)+(ky)=(kx)(ky). This is verified by the following calculatio
A square matrix M is symmetricsymmetric matrix if, for each index i,j, the entries m_{ij} = m_{ji}. That is, the matrix is itself when reflected over the diagonal from upper left to lower right.
-Prove that the set of n \times n symmetric matrices is a subspace of M_{n \times n}.
+Prove that the set of n \times n symmetric matrices is a subspace of M_{n,n}.
@@ -1124,7 +1136,7 @@ Decide if each of the following is a subspace. If so, prove it. If not, provide
Give an example of each of these, or explain why it's not possible that such a thing would exist.
-
A nonempty subset of M_{2 \times 2} that is not a subspace.
+
A nonempty subset of M_{2,2} that is not a subspace.
A set of two vectors in \mathbb{R}^2 that is not a spanning set.
diff --git a/source/linear-algebra/source/02-EV/04.ptx b/source/linear-algebra/source/02-EV/04.ptx
index f0ae851e4..a28996750 100644
--- a/source/linear-algebra/source/02-EV/04.ptx
+++ b/source/linear-algebra/source/02-EV/04.ptx
@@ -664,7 +664,7 @@ vectors that can form a linearly independent set?
Mathematical Writing Explorations
- Prove the result of , by showing that, given a set S = \{\vec{v}_1,\vec{v}_2,\ldots,\vec{v}_n\} of vectors, S is linearly independent iff the equation x_1\vec{v}_1 + x_2\vec{v}_2 + \ldots\ + x_n\vec{v}_n = \vec{0} is only true when x_1 = x_2 = \cdots = x_n = 0.
+ Prove the result of , by showing that, given a set S = \{\vec{v}_1,\vec{v}_2,\ldots,\vec{v}_n\} of vectors, S is linearly independent if and only f the equation x_1\vec{v}_1 + x_2\vec{v}_2 + \ldots\ + x_n\vec{v}_n = \vec{0} is only true when x_1 = x_2 = \cdots = x_n = 0.
diff --git a/source/linear-algebra/source/02-EV/prefigure/EV3-R2.xml b/source/linear-algebra/source/02-EV/prefigure/EV3-R2.xml
new file mode 100644
index 000000000..f5855bd52
--- /dev/null
+++ b/source/linear-algebra/source/02-EV/prefigure/EV3-R2.xml
@@ -0,0 +1,10 @@
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\ No newline at end of file
diff --git a/source/linear-algebra/source/02-EV/prefigure/EV3-planar-subset.xml b/source/linear-algebra/source/02-EV/prefigure/EV3-planar-subset.xml
new file mode 100644
index 000000000..fc4b335c7
--- /dev/null
+++ b/source/linear-algebra/source/02-EV/prefigure/EV3-planar-subset.xml
@@ -0,0 +1,11 @@
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