Using FOIL: $\displaystyle{\left({5}{x}+{1}\right)}{\left({x}-{6}\right)}={5}{{x}}^{{2}}-{30}{x}+{x}-{6}={5}{{x}}^{{2}}-{29}{x}-{6}\usepackage{cmbright}\Huge\$

This is not equal to the given expression. First group terms into pairs and factor out the GCF of each pair. Then factor out the common binomial factor. The correct answer is $\displaystyle{\left({x}+{1}\right)}{\left({5}{x}-{6}\right)}\usepackage{cmbright}\Huge\$ .