Prove that in a parallelogram, the sum of any two adjacent angles is $180°$.

Two adjacent angles of a parallelogram are equal. What is the measure of each of these angles?

In the figure, $\mathrm{ABCD}$ is a parallelogram, $\angle \mathrm{B}=\left(3\mathrm{x}-5\right)°$ and $\angle \mathrm{D}=\left(2\mathrm{x}+35\right)°$. Find the value of $x$ and the value of each angle.

In the figure, $\mathrm{ABCD}$ is a rhombus, in which $\angle \mathrm{BAC}=40°$. Find the measure of $\angle \mathrm{ACB}$.

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In the figure, $\mathrm{ABCD}$ is a rhombus, in which $\angle \mathrm{BAC}=40°$. Find the measure of $\angle \mathrm{AB}C$.

In the figure, $\mathrm{ABCD}$ is a rhombus, in which $\angle \mathrm{BAC}=40°$. Find the measure of $\angle ADC$.

In the figure, $\mathrm{ABCD}$ is a rhombus, in which $\angle \mathrm{BAC}=40°$. Find the measure of $\angle ACD$.