Two loop combination circuit simulated with matrix math

I am trying to find the I1 and I2 (current) of this cicuit using a marix math program.

with the varibles

B1 = +10 V, B2 = +25V, R1 = 12 Ω, R2 = 21Ω, and R3 = 7Ω

I made this bad atempt at it with

I1
I2
B = [10; 25] 
I = [I1; I2]
R = [12 21 7]

In = inv(R)*B

I got stuck on it and am not sure I know what I am doing.

any sugestions or examples would help.

[Sam Chak]

Start by deriving two loop equations using the Kirchhoff's voltage law. Next, rewrite the equations in matrix equation form, A*x = B (which you have already learned in Linear Algebra). Then, solve for x (the currents) using the linsolve() command.

[Sean]

Thank you I will work on it